Another question I need women's honest opinions on

I read something on reddit. It said that women would wonder what is wrong with a guy if he commits early. Like, start thinking they're the only one that wants him and he doesn't have any other options. And then that makes her start thinking he's undesirable, and looking for reasons why other women are not interested in him. Is that just a generalization or is it somewhat true? I mean I guess I'm still inexperienced to some extent, but if this is true then it sort of explains perfectly why my last relationship ended. But idk. Would you see it as a yellow/red flag if I guy was ready to be exclusive early on?