Console emulators are exactly that: emulators. They do their best to be a GameCube, or a PlayStation, but inevitably, it's difficult to be 100 per cent accurate to the physical hardware. Which means you get bugs... weird bugs... like this one, where the doors in Alien Resurrection, a PS1 title from 2000, sometimes wouldn't open, leaving the player stuck forever.
Alien Resurrection can be played on a number of PlayStation emulators and while some of them present with the bug, others work just fine. What's even stranger is that it can also happen on older PlayStation 3s that support backwards compatibility.
You can see the bug in action in the following video:
Not exactly thrilling stuff, but certainly perplexing.
The bug prompted a lot of discussion on various parts of Reddit, including /r/gamedev and /r/emulation. While no one can come up with a detailed explanation, one user by the handle "Sixtyforces" does offer a workaround:
It has to do with audio emulation inaccuracies iirc. I ran into that problem when I made a post here about playing AR with mouse+keyboard controls.
Eternal SPU Audio Plugin version 1.50 or 1.42 fixed the doors not triggering issue. Need to use ASync mode set to SMOOTH.
The idea that it's related to audio emulation matches up with several other opinions, including one that suggests the doors might wait for a hardware signal (so it syncs with the sound effect) and that it could possibly be an anti-piracy measure.
It's funny to think that in order to create the perfect emulator, you sometimes have to do things imperfectly.