In the dating/PUA game (especially early on), it can be easy for guys to doubt themselves, to always assume that they've not reached some sort of milestone or pinnacle yet, to subconsciously feel that he must please the woman rather than vise versa.

One milestone that can be difficult to identify when it becomes an ongoing reality is of becoming a chooser rather than the chosen. Once you've proven to yourself that you can date easier, have regular sex, gain/keep the attention of attractive women, and flirt with women properly you start to realize that women are truly not to be put on a pedestal. You realize that you can start screening women according to your needs/desires and even give them your own shit-tests. Women and men are humans that take many forms, personalities, strengths and weaknesses. Women can be, to certain degrees, just as bad or unattractive (or good/attractive, conversely) as men, every individual man or woman is complex and must be assessed as such. Your relationship with each individual is going to be different as well. This may seem like it goes without saying, but while overcoming any dating inadequacies, many guys (including myself) will pursue any girl that they find physically attractive, seeking to convince her that he is also attractive, without a much deeper regard. This is totally fine if it's in line with your desires at the time and is practiced more/less ethically.

You may reach a point, as I did, where you stop feeling like it, and you get down on yourself for not trying harder to win this or that girl over. You may feel like you've lost it or gotten rusty (which may or may not be true) in the dating game. You may generally notice women won't respond as they did before when you were engaging them more. This is not always a bad thing. I've realized this may be a sign that you've reached a new plateau (or climb). This new/different phase is where you become tired of winning over just any attractive girl and start to become choosier, perhaps taking more complex personality traits into account. This, automatically, limits your dating/sexing/loving pool. A result of this is that you'll find yourself with less quantity in dating but, at least eventually, more quality. This isn't to say that any girl you reject is a piece of shit, or even unattractive, it just means that you've gotten initial physical dating urges out of your system and now require more depth in dating. Perhaps this ebbs and flows as your dating desires fluctuate, perhaps it changes with age/experience, perhaps it changes with mood/the seasons, who knows.

To sum up, if you start to not "feel like it" (as in pursue/date certain girls), despite their physical attractiveness... if you start to feel tired of your previous dating habits, this may not always be a bad sign. It may just be a sign that you've moved on and changed as a man. Many times there's a reason you don't feel like doing something. Why? Because you're just not that into it. This is why some people spend countless hours working on cars, while others spend countless hours practicing music, and still others spend countless hours reading, whereas none of them are moved to take on the hobbies of another. As you become the chooser, you both consciously and subconsciously decide who you feel like investing time in and who you don't. A huge, unspoken part of flirting/dating is testing the waters and seeing if both parties feel like pursuing things further. Sometimes, even small incompatibilities can fizzle out an initial/physical attraction. Sometimes the time/energy/investment in a girl isn't worth the reward, and that's fine.

Hope this lends some perspective and wasn't too verbose! If I'm full of shit, or full of wisdom, lemme know.