There could be a mental health component in some cases.

But most of the time, it's lazy thinking and ridiculous rationalization to avoid taking responsibility for their lives.

The reality is, it has nothing to do with their looks, and everything to do with them not knowing how to attract women.

They never had a mentor, a friend, or someone to show them how. So they go to a party, are too shy to talk to women, and then blame the women for not being interested in them.

So instead of deciding to put in the effort to figure out how to solve this very solvable problem, they decide it's impossible, and it's just easier to believe that women don't like them because of how they look.

Of course, incels hate me for calling them out on their bullshit, and then move the goalposts when I dismantle their arguments, but the only thing that will solve this is taking responsibility for one's life.