I don't think this topic would be allowed over on the official forums as it might violate their Unsportsmanlike Conduct rule that they very liberally enforce there, but after reviewing the rules here seems fine to talk about here. Honestly I think this is a problem that merits discussion, one that BHVR knowingly or unknowingly chooses to ignore.
Over on the official forum if you've read any amount of posts I am sure you have encountered posters who say if you click Ready (paraphrasing here) you sign a contract written in blood that you will give the match your all until it is over. But there is certainly a different subset of players, a type far less likely to post about it anywhere, who view clicking that Ready button as more like getting a lottery ticket to fun. They're hoping to have fun and if they're not having fun they're ready to move on.
This subset of players play completely different depending on the match they're in. If they are on a map they like vs a killer they like who isn't using perks/strategies they don't like and they're not PWYW in a short killer queue, you probably won't be able to tell the difference between them and a "normal" player. They have no reason to "quit."
But if you put one of these players on a map they don't like, vs a killer they don't like, using strategies/perks they don't like and/or they're PWYW & have a 6 minute killer queue they might "quit." Some players it takes even less like getting downed first or they saw a survivor crouching in a corner for 5 seconds and they "quit." Each player from this subset has a different set of triggers and each trigger could be responded to with varying degrees of "quitting."
The Hard Quit. This is when a quitting survivor is completely done with a match, for whatever reason. Best case scenario is they DC and leave a bot to play in their place. If they want to dodge a DC penalty they might run to the killer to get killed, notification-spam to summon the killer to kill them or just AFK.
The Malicious Quit. This is the worst case scenario, which can happen when it's a team mate that annoys them, and they become malicious. A malicious survivor is the type that tries to hinder a fellow survivor in chase, runs around the map dropping every pallet, sells out teammates, etc. (Another type of player can seem malicious but is just doing whatever it takes to get some annoying challenge done, such as picking up downed survivors in the killer's face with For The People to their own & their team's detriment. Or they might forgo saving a team mate that's 30m away from them in favor of sitting on a gen because they have a complete 10 gens challenge and the game already looks like an L anyway.)
The Soft Quit.
This is probably the most insidious and hard-to-detect "quit." This is when a survivor's heart leaves a match because they have been triggered but for whatever reason don't want to quit, because they don't want a DC penalty or maybe they don't want to completely waste their BPS/anniversary cake offering. They might start the match in this state because they're PWYW & only have a 5 minute killer queue. They might have a particular challenge they're trying to get done and once that's done they don't care anymore. This type of "quit" is also more likely from SoloQ gamers as they can just instantly queue up again once they're out of the match.
They're still playing the game but their heart's not in it, their survival or their team's survival doesn't matter anymore. Similar to triggering each soft quit can be different, depending on the player. The most obvious type is the player who just sits on gens and doesn't care one iota about anything else and the killer can walk right up and grab them off the gen, healthy or not. If they get unhooked they might forgo getting healed and just hop on the nearest gen or totem. If they do run from the killer they give a token chase, just enough of a chase so the killer doesn't think they've given up and slugs them like the last killer did. If put on the hook they often forgo hitting the struggle skill checks. They may be more prone to taking on riskier plays because they don't care about the consequences, because they want to be sent back to the campfire ASAP.
It's the state of "I'm stuck here and I am putting in a token performance" sort of play. I bet all Ghoul mains encounter these soft quitters a lot.
Interestingly the opposite can happen too. A survivor might ready up half-heartedly and then lock-in because they get a particular scenario they love such as against their favorite killer on a favorable map.
The Soft Quit is a very insidious problem because it's very difficult if not impossible to tell the difference between a soft quitter or someone who is new/bad or just having an off match. It's not something BHVR can quantify by looking at their stats. And it's a quiet problem, players don't run around advertising they do this.