Of course it have flaws. There's no such thing as perfection in art - there's far too much subjectivity.

I'd say that one of its major flaws is that it's too obvious and saccharin. The characters are mostly pretty one dimensional and built around convenient traits to neatly move the story along without asking much of the audience. They're basically either bad or good - there's little to make me feel like they are real, multi-faceted people.

And then it just feels like they couldn't resist tying everything up in a neat little bow. All the bad guys get their own individual neatly fitting comeuppance. The guy who beats him up gets beaten up (and not by a 'good' guy, as that might be morally ambiguous). The tough-guy prison guard cries as he goes to prison. The hard, evil warden who is responsible for having people killed and keeping people in jail is a coward who can't kill someone himself or face being in jail.

And they then literally follow the characters all the way to paradise, just to deliver the icing on the already overly sweet cake. It feels like an ending tacked on just to please a focus group who required their every question be unambiguously answered.

The whole thing just all feels very conservative to me. Playing it really safe.

Don't get me wrong, I do enjoy the film. But I certainly don't understand why so many people genuinely think it's the greatest film ever, or even just great. Maybe because it's very satisfying, and just gives them what they want?