When you have a series that stars a protagonist who is pretty ditzy and takes quite a while to shape up, there are of course going to be some idiotic moments.
- In the series, different monsters attack the citizens of Tokyo. Usually these citizens get drained of energy, brainwashed, or turned into monsters.
You'd Expect: Tokyo's government officials and police would get wise to this and try to set up damage control, or a task force.
Instead: This doesn't happen, apart from one police chief hiring Sailor V as a part-time cop. People get hurt on a regular basis, and in the manga at least the world ends twice.
- In the first two seasons, Naru Osaka grabs the Distress Ball quite a lot, as does her (eventual) boyfriend Umino. Many youma, two Shittenou, cardians, and droids target her. It's even implied that she grabs the ball due to being best friends with Usagi, who is a Weirdness Magnet.
You'd Expect: Memory loss from season one aside, that Naru would take some self-defense classes after the first several episodes of R, where she got attacked in nearly each one. Umino is shown to be analytical of such situations, and revealed he could hold well on his own against Zoicite for normal human. Mako has shown that you can grapple with magical beings briefly.
Instead: Naru doesn't, and neither does Umino. Thus, they remains easy pickings for many an enemy.
- In the first episode, Luna finds a girl, Usagi, who saves her from some kids. Luna finds out that Usagi is the Guardian Sailor Moon, right as they both sense a youma is attacking Naru. Sailor Moon is understandably hesitant since she's Just a Kid and has never fought before.
You'd Expect: That Luna would tell Sailor Moon about her powers before going to save Naru and confront Morga.
Instead: Luna doesn't because in her mind there's no time and Usagi has to prove herself. As a result, Usagi nearly gets killed and cut by a broken beer bottle. She's able to weaponize her crying, but that's about it.
- In the 9th episode, Usagis Disaster! Beware of the Clock of Confusion!, when Sailor Moon and Sailor Mercury go after the Monster of the Week, Ramua, they eventually pinpoint her location and manage to locate her. However, once they find her, Usagi finds that she can't stand up because the clock has nearly drained all of her energy. After Ramua slices Usagi's cheek with her naginata, she freezes time entirely for Mercury, making her unable to move completely.
You'd Think: Ramua would cast the same spell on Usagi, causing her to be completely immobile. Ramua could then use her naginata to stab Usagi in her head and into her brain, killing her instantly, then finish Mercury, the end.
Instead: She doesn't cast the same spell on Usagi/Sailor Moon, insisting on forcing Ami/Mercury to watch helplessly as she makes Sailor Moon suffer before killing her. Tuxedo Mask, who has already entered the clock store, discovers main clock (that is the entrance to the alternate time dimension) is the source of Ramua's power drain, throws a rose at it, damaging the clock, causing the energy Ramua collected to escape from her, Usagi getting her energy back, and Mercury being able to move again. Mercury uses her Bubble Spray attack and Sailor Moon finishes Ramua with Moon Tiara Action.
- In the 13th episode, Girls Unite! The End of Jadeite!, after Jadeite gets his ass handed to him by the guardians, he reports back to Queen Beryl saying he knows their identities. Beryl, on the other hand, is not pleased with Jadeite's latest failure.
You'd Think: Beryl would at least hear what Jadeite has to say before killing him. A lead is a lead, and even if it was wrong (which, in this case, it wasn't), she at least wouldn't have to deal with Jadeite again.
Instead: Beryl skips the first part and offs Jadeite. Not surprisingly, this comes back to haunt her; the current guardians (Moon, Mercury and Mars) are still alive to mess up their plans, and, by the end, two more (Jupiter and Venus) come along to complicate matters.
- Mamoru aka Tuxedo Kamen wants the rainbow crystals because they can lead to the silver crystal, which will lead to him getting his memory back. He tells the Guardians this while investigating Princess D's own crystal. They are shocked but sympathetic.
You'd Expect: That, given how sympathetic the Guardians are to his cause, and how Sailor Moon owes him for a huge damn amount of rescues, that he would trust them more and ally with them to get all of the seven crystals. It shows that he would surrender the crystals for the girls' lives when Kunzite and Zoicite successfully trap all four of them near the end of the Zoicite arc.
Instead: As Sailor Moon loses her crystal during Hostage for MacGuffin with Zoicite in one instance, and Zoicite gains the other four, Tuxedo Kamen becomes more brusque towards the Guardians and tells Sailor Moon he's not interesting in an alliance after giving her his locket. This means that when he plans to face Zoicite in one-on-one combat, injured and not thinking straight, he only has backup by sheer luck. Usagi insists on coming with him to help after finding out he's bleeding, and the girls in searching for Usagi find him. Even so, they arrive too late to save him from Zoicite, which could have been avoided if he had relied on them. Tuxedo Kamen does learn from this after season R.
In addition: It was Lethally Stupid of Mamoru while stabbed and bleeding to go and fight Zoicite in a one-on-one duel. If he were going to do it, he should have gotten his shoulder treated first. Even Usagi knows this.
- Due to his attempt on Mamoru's life, Beryl executes Zoicite despite Kunzite's protests. Beryl then reveals that Mamoru is Endymion, her former crush and Princess Serenity's beau, thus very important to her. Kunzite can only comfort Zoicite in his last dying moments.
You'd Expect: Kunzite to realize that Beryl is a Bad Boss, and that it's best for him to pull a Screw This, I'm Outta Here! since while Beryl could send a youma after him, it would have a hard time defeating him. He's not Nephrite, after all, hampered by love anymore, and there are many places for a man to grieve and hide from such a pesron. Beryl has a brainwashed Endymion by her side, so she won't be helpless.
Instead: Kunzite blames the Senshi for Zoicite's death even though Beryl points out that Zoicite defied the queen's orders, which is treason. He stays by her side, and reluctantly allies with Endymion.
- After it's revealed that Sailor Moon has the Silver Crystal and that she is the Moon Princess, the villains set up some traps for Sailor Senshi in hopes to find out Sailor Moon's identity and steal the Silver Crystal. Now some traps the Senshi fall into by coincidence, but then we have one tournament that has the name Moon Princess in the contest.
You'd Expect:The girls to be a little suspicious that there's a contest, specifically looking for the Moon Princess. While they should certainly investigate it, it should be with caution.
Instead: They don't bat an eye to the suspicious name and two of them walk into that trap.
- The Dark Kingdom discovers a monster sealed within a lake that's mostly similar to their own, but not quite. Beryl, Kunzite and Endymion ponder over what to do with it.
You'd Expect: Them to at least investigate the monster further before aggravating it, in case it ends up out of their control.
Instead: Endymion awakens it without any regards to why it was sealed there or how powerful it really is, and it tries to kill everyone in sight, Endymion included. And it would have if Sailor Moon had not stopped her, as she was a ghost immune to everything except Moon Healing Escalation.
- Kunzite finds an English cop named Katerina, who worked with Sailor V and knew her secret identity. He compels her to go to Japan, look up Minako. Minako is very surprised to see Katerina because they last saw each other before a building exploded; it turns out that Minako had feelings for a man named Alan, whom Katerina fell for after they thought Sailor V had died. Minako tearfully made the decision to let them think she died, and moved to Japan to help out the other Senshi there, because she loved Alan but she didn't want to hurt either of them.
You'd Expect: Kunzite would have turned Katerina into the youma Papillon to trap Minako before she can transform, incapacitate Sailor V while she's powerless, and then interrogate.
Instead: Katerina asks Minako about who the Sailor Senshi are and presses her for information. She tries to justify it by saying she's a cop.
The Result: Minako makes an excuse and leaves Katerina's hotel room, trying not to cry. Kunzite only then turns Katerina into Papillon, and Minako manages to transform into Sailor Venus and fight back. While she does get captured, it's brief since Artemis told Usagi to look for Minako, and Usagi manages to rescue her. Then Usagi nearly kills Papillon on hearing about Katerina "stealing away" Alan, and Minako barely managing to convince her to heal Katerina instead.
- In the Season 1 finale, the Senshi travel to the North Pole to face Queen Beryl. Beryl sends out her most dangerous youma, the DD Girls. The youma, who can create illusions of the Senshi's love interests in distress, manage to isolate Jupiter and engage in a Mutual Kill. By the end of it Mako and two of the DD girls are dead, but Sailor Moon is horrified and grieving. Ami has to smack her to get her to stop rambling about surrendering the crystal for her friends' lives.
You'd Expect: The Senshi to realize that it's safer to stick together and to take on the DD Girls at once while walking to the Dark Kingdom's base, and that Sailor Moon won't be able to fight if she's grieving for her friends. Mako died because she stayed behind to launch at lightning attack, with Mars and Moon unable to attack without getting her hurt. The girls now know that if they see their loved ones it's an illusion.
Instead: All of the Senshi invoke More Expendable Than You to a traumatized Sailor Moon, and prioritize destroying the youmas' illusion powers. Ami stays behind and dies after she destroys the DD Girls' illusion crystal, while Minako does Taking the Bullet when the youma target a Heroic BSoD Sailor Moon. Rei then refuses to let Sailor Moon help her defeat the two surviving DD Girls, which leads to her getting killed. Sailor Moon after seeing all her nakama die can barely get herself up and going to the Dark Kingdom Base, where she has to fight a brainwashed Mamoru and then a Metaria-possessed Beryl. By the second season, the trauma from this battle affects her ability to fight, which nearly gets her and the Senshi killed again.
- At the end of Season 1, after Usagi dies defeating Beryl, her last wish was to have a normal life, which results in reviving everybody, but at the cost of her and the other Inner Guardians losing their memories about being friends with each other. As seen in the next season, Luna and Artemis can restore their memories.
You'd Expect: Luna or Artemis (more likely Luna, as she does this in R) to restore the Inner Guardians' memories (without the "reawaken them as Sailor Guardians" bit, so they could still live normal lives). It wouldn't hurt to have their memories of their friendships restored, without having to be Sailor Guardians, considering that Usagi's friends had pretty lonely lives before she came into their lives (as it was seen in some flashbacks in the R movie).
Instead: They do absolutely nothing of the sort, and let them live without their memories of being friends for for two/three months. It isn't until when the Makaiju aliens attack, does Luna restore their memories, and also reawaken them as the Sailor Guardians. Sure, Makoto/Jupiter and Usagi already had become friends anyway when the R season began (implying Usagi did approach Mako despite the rumors, just like in her first apparition) and were in cordially talking terms with Ami/Mercury (made possible by the fact that they attend the same school, and rather important for Ami since she was often shunned by other students)... but had the events of R not happened, Usagi's other two Senshi friends would've probably spent the rest of their lives in their depressing pre-meeting-Usagi lives note (as seen in the aforementioned flashbacks during Fiore's rant to them in the R movie): Minako (Venus) being thought as a stuck-up Sailor V wannabe, and Rei (Mars) being considered a freak for her psychic powers and devotion to her grandpa's temple!
- In the first episode of R, Ail and An send a Cardian monster to steal human energy for Makai tree. Luna and Artemis see the aftermath of a victim of a monster attack. Those strange feelings that she had were right. There is a monster on the loose. Artemis suggests that they restore the Sailor Guardians' memories and re-awaken them.
You'd Expect: Luna to say "yes" to the idea. After all, the situation is no longer peaceful or normal. Plus, there's a limit to what Artemis and Luna could do in terms of combat, since they're just cats.
Instead: She immediately shoots down the suggestion, saying that the Guardians are leading peaceful lives. They try to fight the monster by themselves after it attacks Naru, but to no success. It's only when Artemis puts himself in danger by distracting the monster does Luna realize that there's no choice but to re-awaken Usagi as Sailor Moon and restores her memories.
- In the following episode, after Usagi demonstrates that she is still not quite competent on her own, Luna ends up having to re-awaken Ami, Rei, Makoto, and Minako as Sailors Mercury, Mars, Jupiter, and Venus respectively. After that, all that's left is to restore Mamorou's (aka Tuxedo Mask) memories.
You'd Expect: Luna to do the same memory-restoration thing she did to the Inner Sailor Guardians to Mamoru, or at least attempt it.
Instead: Luna never thinks of doing the same procedure to Mamoru, nor does Usagi suggest it to Luna, which would've probably solved the amnesia issue rather quickly, instead of dragging it for 12 or so episodes. Even if it's not possible to do this to someone from the Earth Kingdom rather than the Moon one, it could've been worth a try at least. Mamoru's subconscious solves it by creating the Moonlight Knight, and he eventually recovers his memories at the end of the Makaiju arc, but still.
- In the 61st episode of R, Mamoru Chiba starts freaking out after he has a dream where Usagi will die. And not only that, he has it several times. All of this takes its toll, and he dumps Usagi to avoid exposing her to danger.
You'd Expect: Mamoru to eventually tell Usagi straightforwardly that he's got big issues of his own to solve and needs some time out to figure what the heck is going on. Maybe not tell her the content of the dream, but he could at least let her know that the blame's not on her.
Instead: Not only does Mamoru dump Usagi without any decent explanation, but he actually does everything in his power to push her away for 16 episodes, sometimes even resorting to borderline psychological abuse... and still refusing to tell her why he let her go. The result? - the confused Usagi flickers between being determined to become strong enough to win him back and being so depressed that the enemy takes advantage of her fragile state of mind and almost kills her in Episode 69. And even after Mamoru saves Usagi from the sleeping death in that episode, he STILL doesn't explain or get back together with her for an additional 8 episodes!
- By around the 73rd episode of Sailor Moon R, Chibi-Usa has been in the dark about Usagi and her friends being the Sailor Senshi. She only manages to learn about it by accident around the time they go fight Petz and Calaveras after Kooan and Bertier's Heel Face Turns.
You'd Expect: Chibi-Usa to wait before doing anything drastic, or to call Sailor Pluto who is stuck at the Gate of Time but is still able to give her advice. Or even to confront Usagi and the girls on the whole deal. Usagi's Transformation Trinket holds the powerful Silver Crystal and she's the only person able to draw its potential, so Chibi-Usa can't afford to not ask her for help with it.
Instead: Chibi-Usa throws a hissy fit upon seeing Usagi keep her brooch around carelessly and steals it to return to the future with the Silver Crystal. She even whines to herself in her inner monologues about how Usagi is an idiot and how much she hates her! Predictably, Usagi cannot transform and without her, the Sailor Guardians are easily kidnapped by Rubeus, leading Usagi to almost slap Chibi-Usa around for being so stupid.
- In episode 74, Defeat Rubeus: The Battle in Space, Usagi transforms into Sailor Moon and voluntarily surrenders herself and Chibi-Usa (who goes with Sailor Moon to make up for her previous mistake of allowing the other Sailor Guardians to be kidnapped) to Crimson Rubeus so that she can board his ship and rescue the other 4 Sailor Guardians who were kidnapped in the previous episode. When she confronts him, it becomes quite difficult for her to fight him, due to the fact that he can mess with the gravity using a power amplifier to adjust the gravity of the ship. He first makes her feel heavy with super gravity, then adjusts to turn the gravity off and sends Sailor Moon floating high above, then turns the super gravity back on again, enough to make her sink into the ground. However, against all odds, Sailor Moon stands up against maximum gravity, but it's still difficult for her stand nonetheless.
You'd Think: Rubeus would keep the super gravity on, and finish Sailor Moon with his energy attacks. After all, even though Sailor Moon managed to stand up despite maximum gravity being turned on, she still is slowed down by it, and is thus an easy target for his energy attacks, which he can use to shoot her to death. Then he can kidnap Chibi-Usa, The Bad Guy Wins.
Instead: He turns the super gravity off for absolutely no reason. And because of this, Sailor Moon is able to use her Moon Princess Halation attack to deflect Rubeus's energy attack with little difficulty.
Continuing On: Chibi-Usa can't get through the barrier where the crucified Sailor Guardians are, but she does discover the power amplifier that is the reason why Rubeus is able to mess with the gravity, keep the barriers in place, be able block Sailor Moon's attacks, and is also the source of Rubeus's super powers. Chibi-Usa goes Plucky Girl due to blaming herself for what happened, so in an attempt to atone she grabs on the amplifier and, since she's just a little girl and the crystal exudes bad energy, she painfully struggles to get it out. At some point, Rubeus manages to overpower Sailor Moon's Moon Princess Halation and knock her into a wall, knocking her out for a tiny bit.
You'd Then Think: Rubeus would quickly finish Sailor Moon off with a shot of dark energy to the head or something, killing her. He could then kill or capture Chibi-Usa and prevent her from fully taking the power amplifier out, handing her to the Black Moon and then guaranteeing his victory.
Instead: He just assumes Sailor Moon is completely dead or incapacitated and turns his focus to Chibi-Usa, who's still struggling to get the amplifier out. Unfortunately for him, Sailor Moon is continues hitting him with more shots of Moon Princess Halation, taking his attention away from Chibi-Usa, who then manages to pull the amplifier out while Rubeus is distracted, causing him to lose his power and get hit by Sailor Moon's attack.
The Result: Mercury, Mars, Jupiter, and Venus are saved. Because the ship has lost power, it starts self destructing, but Sailor Moon, Chibi-Usa, and the other Sailor Guardians manage to escape by using Sailor Teleport to teleport back to Tokyo. Rubeus, however, is not so lucky, as he is left to die on his exploding ship by Green Esmeraude for his failure.
- Mamoru's future self King Endymion is in a VERY difficult crossroads since his daughter Chibi-Usa is in the past, Neo Queen Serenity (Usagi's future self) is in a coma, the Guardians have improvised a Barrier Maiden stunt to protect what's left of Crystal Tokyo, and he himself is now little more than an astral projection. Endymion still has his memories of how his life was in the past, and wants to help his former self....
You'd Expect: For him to send Mamoru very clear warnings about the future and tell him what's going on. What's left of his powers allows him to alter Mamoru's dreams and communicate with him, even if he can't directly tell him all that has been going on.
Instead: He tests Mamoru and Usagi's bonds, which are somewhat stronger than in the past, but still shaky, via mind-raping his own younger self with vague dreams about how he must dump Usagi to save her from a Bad Future. Which leads to needless melodrama, bad decisions, stress and heartbreak for both Usagi and Mamoru. It's not until Usagi has a dream about it as well that things are a little cleared up, and once they meet in the future, neither Mamoru nor Usagi stay angry at Endymion for almost destroying their relationship in the first place Tuxedo Kamen does charge him, and Sailor Moon starts to call him out before he explains that he's in a coma and thus they only see an astral projection.
- In the first episode, Rei has an ominous dream about the world being destroyed by a mysterious force.
You'd Expect: Rei to tell her friends about his immediately. Even if they were enjoying a couple of months of peace, if the dream foretells the coming of a deadly enemy, then they need to be prepared as soon as possible.
Instead: While at first, Rei starts to tell the others about her dream, she decides against it, thinking it doesn't mean anything. The others only find out later in the season when Setsuna tells everybody that she, Rei, Haruka, and Michiru have been having the same premonition.
- In the fifth episode, Protect the Pure Heart! A Three-Way Battle, Ami uses her mini supercomputer to track Unazuki's Pure Heart Crystal after it had been stolen from her.
You'd Expect: Ami to use her supercomputer more often, especially to potentially find out who the owners of the Talismans are.
Instead: Ami doesn't use her supercomputer again after this episode, in spite of how useful it is.
- After Eudial contacts Haruka and Michiru, having learned of their identities in the previous episode, to let them know that she has found a Talisman, they decided to confront her.
You'd Expect: Them to assume she is trying to lure them into a trap and be on their guard.
Instead: The possibility that it's a trap doesn't enter their minds as they are more worried about how their hands will become dirty and that their mission is close to completion. As a result, Uranus and Neptune turn out to be the Talisman holders and if Usagi had heeded their threat and decided not to follow them, they would've died and the Death Busters would've gotten their hands on two Talismans.
Continuing On: Before they left to confront Eudial, Haruka and Michiru called Usagi to meet them, telling her not to interfere with their task.
You'd Expect: Haruka and Michiru to leave their refusal of Usagi's assistance at threatening her.
Instead: Haruka and Michiru don't just threaten her, they forcibly take her transformation brooch away from her, with the Silver Crystal inside. They had brought an incredibly powerful crystal to the location where they would meet an enemy, and while there were no consequences to this action, had Eudial discovered the brooch containing the Silver Crystal, the Death Busters would've obtained a crystal that has been stated to have the power to destroy an entire planet.
- After Chibiusa's Pure Heart Crystal is stolen by a possessed Hotaru, the evil entity controlling her was revealed to be Mistress 9, not Sailor Saturn, and the other Senshi realize that Hotaru had been possessed by a Daimon the whole time.
You'd Expect: Sailor Moon to use the Silver Crystal to free Hotaru from Mistress 9's possession, as she had used it in the previous seasons to return the carriers of the Rainbow Crystals to their human forms, freed Mamoru from Metallia's control, purge the evil from the Spectre Sisters and turn them into normal humans, and purged the evil from Black Lady and turned her back into Chibiusa. Purging evil from a person or place has been a power of Sailor Moon's since the beginning and it's a power that doesn't drain her of her energy, so it would stand to reason that this would be able to save the world and defeat the enemy without sacrificing Hotaru.
Instead: The Silver Crystal isn't even mentioned as a possible option in defeating the Death Busters or saving Hotaru, with it's last mention being the second episode of the season where Usagi worried it had lost its power after her transformation came undone. It was revitalized by her and Mamoru's love and allowed her to transform again after her brooch became the Cosmic Heart Compact, but it's never mentioned for the healing powers it is known for, resulting in a lasting dilemma over whether Hotaru can be saved or not.
- Near the end of the season, Mistress 9 awakens and takes over Hotaru's body. She temporarily reverts back to being Hotaru, claims Hotaru's body is rejecting her and asks Sailor Moon to give her the Holy Grail, despite the Outer Senshi pleading with her not to.
You'd Expect: Sailor Moon to be on her guard and refuse to hand over the Holy Grail. She already has realized that Mistress 9 is the one in control and not Hotaru, since she committed the mistake of mentioning the Senshi while in her Hotaru form, something Hotaru could not know about.
Instead: Sailor Moon gives the Holy Grail to Professor Tomoe, who passes it to Mistress 9. She places it in a device, the Holy Grail is destroyed, and all hell breaks loose as Pharaoh 90 appears and daimons swarm Tokyo. It's only through the apparition of Sailor Saturn, Hotaru's actual other self, that Moon manages to have anything similar to a way to fix up everything.
- Related to the above: While Mistress 9 is still more or less dormant, Hotaru is taken care of by her Brainwashed and Crazy father Souichi Tomoe. Tomoe's assistant Kaori "Kaolinite" Naitou, for some reason, really hates Hotaru, probably out of jealousy since she's in love with Professor Tomoe who, while off-work, pours his attention on Hotaru and especially when Mistress 9 is speaking through her.
You'd Expect: For Kaolinite to suck it up and treat Hotaru differently, since she is Mistress 9's host and no one can replace her.
Instead: She verbally abuses Hotaru, was implied to have killed her pet fish as a child, and is a terrible caretaker. Obviously, once Mistress 9 feeds on Chibi-Usa's Heart Crystal and fully awakens, one of her first actions is killing Kaolinite on the spot. What, did she think that 9 would just forget what she did to her host? Moron.
- In episode 14, The Brightness of Calling Stars! Haruka and Company Into the Battle, Sailor Moon thanks the Starlights for always coming to her aid and asks if they could team up.
You'd Expect: The Starlights to agree, considering they have had no quarrels up to this point, have helped to weaken the Phages, have directly saved Sailor Moon's life on several occasions, have acknowledged Sailor Moon to be powerful and quickly abandoned their previous beliefs in killing the Phages when they realized it, and have a common enemy in Galaxia.
Instead: The Starlights do agree to be allies, but just as Sailor Moon and Sailor Star Fighter are about to shake hands to seal the deal, Sailor Uranus and Sailor Neptune interrupt, refusing to be allies with the Starlights since they are invaders from outside the Solar System, leading to tension and mistrust between the two Senshi groups for the rest of the season.
Continuing On: Uranus and Neptune notice the Starlights with Sailor Moon and immediately want to separate them.
You'd Expect: Them to make their presence known without making any rash actions.
Instead: Just as Moon and Fighter were about to shake hands, Uranus launches her "World Shaking" attack at them. While she was aiming for Fighter, Sailor Moon, the princess who they said they wanted to protect, was standing right next to her and was dangerously close to being hit her by attack.
- In episode 28, Holy War in the Galaxy! Sailor Wars Legend, Princess Kakyuu tells everyone about the legend of the Sailor Wars and how the ultimate threat in the galaxy, a being called Chaos, had been sealed away by a legendary Sailor Soldier, but has now reemerged as Galaxia who plans to collect all the Star Seeds in the galaxy. Princess Kakyuu says there is a chance to save the galaxy if they can find the Light of Hope, which she came to Earth to find, and asks for Sailor Moon's help. Uranus and Neptune soon arrive on the scene.
You'd Expect: Uranus and Neptune to agree to a team up this time since Chaos and Galaxia are a threat to the galaxy, and a threat to the whole galaxy makes it a problem for everyone in it. A team up between all the Senshi would've stomped that threat out in a more efficient, and maybe even quicker, manner.
Instead: Uranus and Neptune refuse to allow Sailor Moon to help, calling Princess Kakyuu selfish for asking such a thing. As a result, very unfortunate events follow.