Think about this: She came before Marilyn Burns in The Texas Chainsaw Massacre and before Jamie Lee Curtis in Halloween. Many people say those two pioneered the Final Girl trope.
But really, when you think about it, it was actually Suzy Kendall who started it.
Actually, I think it was probably Lila from Psycho who actually pioneered it. She was investigative like most final girls are and was the last to confront the killer at the end. And, even though Psycho wasn't really a slasher film, horror fans still credit it for pioneering the slasher subgenre so that would make Lila the pioneer final girl, honestly. It's just an opinion though.
sharePsycho was far better with regards to this, and Lila far more proactive than Jane, who literally only ever did anything useful when it didn't actually matter. Most of the time she, like pretty much everyone else in the film, stood around doing nothing intelligent, exactly as the previous poster pointed out. She was an awful "final girl", but a good example of why the trope of the "final girl" is often so problematic.
Jane was at times fairly realistic for an average person, although most of what she did was just asinine. She was lucky, that's about all. She showed absolutely no initiative in fighting back, never once moved proactively to stop the killer, and basically put herself in harm's way at every opportunity. She was also, lest we forget, stupid enough to fall down the stairs. And what kind of moron couldn't think to slide down a banister when in arm's reach of a murderer and subsequently didn't even bother grabbing one of the weapons right there in plain sight when pursuing the killer?
Jane is one of the worst examples of a horror film survivor because she only survives out of sheer dumb luck and chance.