- For an all-powerful, hyper-intelligent supercomputer, Skynet's plans are incredibly convoluted. Over the years, many people have pointed out all the ways Skynet, with its unlimited resources and supposedly limitless intellect, could have killed John Connor or even the Human Resistance outright. This was forgivable in the first two movies because time travel was spoken of as a last-ditch effort, so Skynet didn't really have much time to plan. However, with each subsequent movie, book, comic, series, etc. that's released, the time-travel-was-a-desperation-move aspect gets retconned further and further, meaning that Skynet has essentially unlimited time to plan. This has the adverse effect of making the central premise of the series not only less believable, but harder to keep straight, since time travel theorems are both way over the average audience member's head and very easy for writers to screw up.
- In general, Terminator 2: Judgment Day kicked off many of the franchise's worse trends. While the first film was a low-budget sci-fi horror film, T2 was a big-budget Actionized Sequel, due in part to the Sequel Escalation involved in making a Terminator the hero. However, T2 was still genuinely scary at points, with the T-1000 being a memorably frightening antagonist, and the non-Terminator characters remained vulnerable despite their Action Survivor status — plus having the Terminator do a HeelFace Turn was genuinely pretty amazing to see at the time. Later films, books, and other media would jettison the series's horror/slasher elements entirely, to the point of being straight-up action films with action-star protagonists.
- Skynet goes through quite a bit of Villain Decay throughout the series as it gradually becomes clear that using Terminators is a horribly inefficient way to kill people. After Skynet's failures in the first two films, the Terminators practically become The Artifact, as one naturally wonders why their masters can't come up with other ways to beat the humans—like radiation, chemical weapons, or biological agents, which are harmless to machines but deadly to humans. The inefficiency was excusable in the first movie, partly because the series' trademark Ridiculously Human Robots were still a novel concept, and partly because it was heavily implied that (like Time Travel) the Terminators were experimental weapons used as a last resort after the Resistance arose from nothing and wiped out most of the Machines' resources. Even when we got another Terminator villain in Terminator 2: Judgment Day, it could be forgiven because it was actually an improvement over the T-800, making it seem like Skynet actually adapted and learned from its previous failure. But after that, future Terminators like the T-X and Cromartie largely became rehashes of the originals, and it became less forgivable when Terminator Salvation and Terminator Genisys made it clear that Skynet knew what would happen in the future, and was actively preparing for it. It also didn't help that Terminator: The Sarah Connor Chronicles made it clear that several Terminators' have unshielded nuclear fuel cells, essentially making them walking nukes, but they apparently needed machine guns and knife-hands to kill humans. This trend reached its low point in Genisys, where Skynet changes things up by inventing nanomachines that can infect humans... then uses them to make another Terminator that can only infect one person at a time.
- Many fans like to criticize the later installments for gradually sanitizing the series of its overt sex and violence in order to reach a more general audience, leading to Bloodless Carnage and a generally Lighter and Softer tone. In particular, they're likely to complain about Terminator Salvation and Terminator Genisys being rated "PG-13", and Terminator: The Sarah Connor Chronicles being a primetime network television show. In fact, though, the franchise has been going in a progressively more family-friendly direction as far back as Terminator 2: Judgment Day, widely considered the best film in the series. Though it is indeed rated "R", Judgment Day has none of the explicit sex or romance of the original The Terminator, its protagonist is a mouthy 10 year-old boy whom the kids and teenagers in the audience can easily identify with, and the plot heavily focuses on the child protagonist bonding with his distant mother and finding a surrogate father figure. And despite its "R" rating, Judgment Day had merch directly marketed to children and teenagers: it had tie-in action figures advertised during kids' shows, as well as its own ride at Universal Studios. Terminator 3: Rise of the Machines had older characters than its predecessor, but it was also more comedic than its predecessor, and its plot similarly revolved around a twenty-something loner bonding with his old high school crush. After that, getting bumped down to "PG-13" was par the course for the series.
- This perception also varies depending on the country. The USA's "R" rating doesn't actually fit in with the majority of national rating schemes, with most having ratings for 18 and 15 (or 16). That meant Terminator 2 actually had a lower rating than the first film in most of the world, being the first time minors were allowed to view the franchise at all, making it much more obvious that it was marketed at a younger audience.
- The way Skynet resorts to increasingly advanced Terminator models to add to the menace. The original film had the T-800. Terminator 2: Judgment Day added the T-1000, and Terminator 3: Rise of the Machines included the TX model, and so on with each subsequent installment in the franchise. But since the most iconic character of the franchise is Schwarzenegger's T-800, they have to include it, preferably helping the good guys. This has the problem of having to make an increasingly obsolete machine somehow helpful against its increasingly superior iterations, and even pivotal to each installment's plot. You'd think that Skynet would eventually figure out a way to neutralize the several T-800s hijacked by the Resistance every now and then.
- According to Word of God, the Terminator saga was always supposed to take place in a changeable timeline, and it was always supposed to climax with the heroes successfully stopping the birth of Skynet and rewriting history. Unfortunately, budget constraints forced James Cameron to save that spectacular climax for the sequel, with the original instead ending with a Stable Time Loop implying that John Connor's birth and the rise of Skynet were both inevitable. So when the heroes actually did seemingly stop Judgement Day, it made it look like the movies just had inconsistent rules regarding time travel. But it was easy to forgive that, partly because the heroes' victory at Cyberdyne made for a great Grand Finale, and partly because the idea of Kyle and Sarah being destined to conceive humanity's savior made for a great love story—even if those two plot points seemed to contradict each other. Many fans were unhappy when Terminator 3: Rise of the Machines claimed that Judgement Day really was inevitable all along. Not only was that idea not planned from the beginning, it also undid T2's ending.
Franchise Original Sin / Terminator