These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Ear Worm: The musical contains among the most memorable songs inspired by 1950's gospel and Motown movement in theatre history, and nearly all of them are catchy.
I Liked It Better When It Sucked: In 2003, a broadway production of this opened, which starred Hunter Foster as Seymour, had a much bigger budget and a more elaborate stage set, with a full orchestra. This was not reacted to warmly by people and was deemed a bastardization; the morals were gone and replaced with a more Disney-esque feel, and the strings and shimmery chimes seemed to get in the way of the rock feel the tracks had. Furthermore the actors didn't fit, and at times were obnoxious, and people were more partial to minimalist stage sets as used in school productions and even the off-broadway production, which seemed to make it more "warm" and intimate to the audience; this production closed down less than a year later due to poor reaction. It wasn't all bad though; the cast recording was often a big seller because it included demos of excised songs from the original production (Bad, The Worse He Treats Me, We'll Have Tomorrow, A Little Dental Music) sung by Howard Ashman, and still continues to sell today for such a reason.
Adaptation Displacement: Fans of this movie are not aware of the Roger Corman movie it was based on, and are disappointed when they rent or download the original, and find out which one they're watching. To an arguably lesser extent, it has displaced the stage musical.
Alternate Character Interpretation: Seymour Krelbourn. Is his letting Orin suffocate from laughing gas revenge, or is it due to him being in shock? Is him letting Mushnik being eaten by the plant because Seymour forced him to walk into the plant, or was Mushnik's backing up into the plant's mouth an action on his own accord?
The movie actually encourages this, as unlike the musical Seymour is never shown actually enjoying his newfound success built on the bodies of Audrey II's victims. This is likely a big reason why the ending had to be changed.
Ending Fatigue: As faithful as the original ending was to the stage musical, it drags. The ending consists of two long musical numbers back to back, the first with Seymour getting eaten by Audrey 2 and the second consists of Audrey 2's army destroying the world. The sheer length of it all may have contributed to test audiences being turned off.
Nightmare Fuel: Audrey II, naturally. But also that a new Audrey plant is seen smiling at the end
Special Effects Failure: In a movie with such good special effects, its one notable flaw stands out; during the scene where Seymour electrocutes the plant, a digitally added explosion is placed over it and the plant simply disappears.
Visual Effects of Awesome: The Audrey II puppet is possibly one of the most complex animatronics of its kind, and still holds up to this day. Frank Oz wanted to direct this film for a reason!
There's also the take over scene in the original ending. All of that was miniatures and puppets!
What Do You Mean, It's Not for Kids?: Through the haze of the years, it's easy to think this movie as a little less grim than it actually is - you remember the songs and the jokes, and the fact that the ending is happy. But parents who haven't watched the movie recently should beware:
If your child is afraid of the dentist, you may want to skip that part.
The scene where Seymour chops up Orin and feeds him to the plant, which laughs with its mouth full of Orin...
That scene actually could've been worse, as props of Orin's head and arms were crafted. Oz decided at the last minute that it was too gruesome and had the props wrapped in red-splattered newspaper for the scene to obscure them.
We actually see the plant swallow Mr. Mushnik whole and later attempt to do so with Audrey.
This applies even moreso to the play, where the protagonist actually murders multiple people, all of the main characters die at the end, and the world ends.