Just my N=1 here, but I've actually run the self-improvement gamut and got results out of it - had a year where I went from never having held hands with a girl to sleeping around quite a bit. I think the self-improvement type of vibe tends to attract girls who are more into short term things, which leads to burnout. By this I mean, if you are a guy who looks very good/masculine, are good at flirting, etc but just are not the type of guy that a girl would want to bring home or show to friends due to some immediately-visible perceived deficiency (like race, height, etc.), you become typecast as the "experiment" (i.e. an easily-accessible alternative to what they normally go for, a one-time thing), the "rebound guy" to get over an ex, or part of a girl's "exploratory phase", etc. - you aren't a priority for her and she cares less about you than the already-little amount you might care about her.

After getting burned a few times I realized that what I "wanted" was to sleep with a lot of girls, but what I "actually wanted" was to sleep with a lot of girls who want me more than I want them (i.e. an egotistical drive) - emphasis on the "want me more than I want them" part. It's an important distinction, and the fantasy is to be the guy who all the "good girls" (i.e. the relationship-oriented girls who don't easily fall for guys) fall deeply in love with and would do anything for but can't pin down, and this narrative is pursued as a goal because it provides a sense of security ("there will always be people who love me"). In reality you just attract many girls who might not even want a relationship, and that fantasy sense of security will cease to exist. Even if you do find the fabled "good girl" or if one of the short-term minded girls falls for you, you will be conditioned to be skeptical and doubtful of their long-term relationship capacity because of your experiences with the other girls, thus erasing any of the sense of security that you initially sought.

Also, in the end it seemed that the "want me more than I want them" thing was actually more important than sleeping with the girls. So when I found out that the girls I was sleeping with wanted me in a relationship capacity less than the admittedly close-to-zero amount I wanted them, it was really demoralizing, as I'd inevitably end up with this weird shitty feeling of being "just another guy" a girl slept with and it did not feel good at all. Then I realized that my behaviors probably also led girls to feel hurt in this way, and the whole exercise between the genders is kind of futile overall and people are hurting each other over something as trivial as ego and a misguided search for security.

Now I just kind of maintain the self-improvements from before, as they've added great value to my life, but I don't actively seek out dating, going to clubs, etc. I figure that if something pointing to a relationship comes about organically I will definitely be fully open to it, but it is not as much of a priority at the moment.