I used to be the quiet, shy boy. Then I was conscripted and I turned into a cocky, rude shithead.
I wonder if I was always like this in my core.

The idea of self improvement when done for the sake of attracting a partner is merely a way to distract a man with trying to reach some unquantifiable "enough" until the point he is too old to do anything about the fact he was lied to. And it's an excellent lie, as it does not have a perceivable end point and so you can be led by the carrot on the stick for as long as necessary. This is also the reason they only list the vaguest of reasons;
>You're an asshole
By who's metric? I see plenty of assholes with girlfriends, guys who literally beat their girlfriends, so clearly I must be someone's definition of "not an asshole".
>You have poor hygiene
Okay, what's "enough" hygiene? Do you mean basic hygiene like showering regularly, brushing my teeth, using deodorant, etc. or do you mean I should have a hefty skincare routine with daily moisturizer, exfoliant, sunscreen, etc?
>You don't ask girls out/you don't ask enough girls out
The first part is a lie, but what of the second? How many is "enough" girls before it gets to the point it's something else? 5 girls? 10? 100? 1000?

The answers to these questions will be just as vague because none of it is genuine advice, it's all just a cheap distraction. They want you to improve, improve, and improve in meaningless ways seeking the mythical "enough" that you will never reach so they don't have to acknowledge the reality that genetics plays a role in it and some people are predisposed to failure, and hopefully by the time you catch on to the fact that they were bullshitting you you'll be 40 and on the verge of killing yourself so that the problem will solve itself.