I can see that a lot of these men might just be trying to come to terms with the fact that they've got no chance of winning the dating game, even if I assume that (even on this site) on this site there are probably a good few men who have come to the conclusion that a marriage will more likely than not make their life worse regardless of their own status, whether that is sour grapes thinking or not. I think the term "Incel" when used as it commonly is refers to a man that is still trying but isn't succeeding due to being unaware of his own failures as a person, hence why it is often thought to be closely related to/synonymous with the white knight, simp and "I'm such a nice guy" archetypes.

And yeah, if you had a bad relationship the first time, it's understandable someone would not want to try again.