STOP HAVING FUCKING HOPE, IT'S NOT GOING TO HAPPEN FOR YOU
This isn't true, except that actions and attitude make it so.
No, women are not mind readers; they cannot always determine if a man is going to be good or terrible. There are a few tells, however; red flags women (and men) are mistaken to ignore:
1) He's rude to customer service staff
2) He's controlling or/and condescending
3) he bad-mouths his ex
4) he bad-mouths strangers based on their appearances
There's also instinct, gut feeling, which both women and men have. A lot of people have ignored their instincts to their regret.
Not only do incels set off that alarm in people, but we have quotes here of some incels who do it deliberately by staring at women or otherwise actively going out their way to make women feel uncomfortable. (And hanging around a shitty forum where men talk about women as if they aren't human bleeds through into their awkward conversations with women, duh!)
There's so much more can be said on this, but what's the point? Incels, who claim to be unbearably ugly on the outside and yet who balk at the idea of dating their "looksmatch", are generally hypocritical, totally self-absorbed, and vain to the point of parody. Under other circumstances, they might be forgiven this because they are often young, but not here: They have absolutely no empathy for young women who make age-related mistakes of their own.