I wanted to come back in and mention the horrible plot holes and technical wrongs that destroy immersion in Alien 3 -- and I find that Jeyl already mentioned many of them. It simply doesn't work as a sequel to Aliens. The more you remember about Aliens, the worse Alien 3 runs, until you have an urge to stop the movie and make sure you saw what you just saw. I don't know what you call the opposite of immersion, but that's it.
There's still meat on the bone, though, when it comes to plot hole. Let's not forget that Alien 3 is the first movie of the franchise to committ the Great Sin of Xenomorph Portrayal, one repeated in all video games and subsequent films to come:
Xenomorphs that pointlessly kill.
Instead of capture and impregnation/conversion -- the point of the "rape monster" motif -- Alien 3 and its worthless spawn present xenomorphs that just bite you for no good reason. The entire point is missed. Contrary to Jim's claim that Alien 3 expanded the biological depth of the xenomorphs, the movie instead narrowed it, unmooring the creature from its base concept and making it an utterly generic boogeyman, a tedious, screeching pit bull with a penchant for crawling. This is one of the reasons the Aliens video games have been so terrible (only one of the reasons. . .). The Jaguar version of AvP is the only one that presents the ability to convert victims to xenomorphs (a properly-executed melee combo turns the victim into an egg which is then used as an extra life for the PC: not terribly elegant, but it gets the theme across). Even the superior, original AvP for the PC doesn't feature this concept. AvP 2 gave us "lifecycle" mode, where xenomorph players start as eggs, move around as nymphs (facehuggers) and have to find a victim to infect. . . during a deathmatch. It's gimmicky and cumbersome and unbalnced, as you might expect. There's no concept in any of these games of the xenomorphs working together to reproduce.
And we have Alien 3 in part to thank for that.