Women "disappointed" by beta men do not date beta men. It is something that only happens once or twice and it is over forever. They certainly do not continue to date and become further disappointed by such men.
No.
This woman is disappointed by men who come off as alpha up front but eventually show their beta stripes. As
@soulforge has said, they are slowly breaking such men down over time, and the reason is because they are setting you up for the ultimate test.
Right now, she is feeding on & fueling your alpha behavior, those thoughts, those actions. She likes them. She is proclaiming how refreshing it is. YOU spin plates. YOU are not looking for the LTR. Things will seem to go well between the two of you for months most likely. She's a plate. You're feeling great. Sex is great. No relationship here. Nope. Just fun and you're reveling in it. YOU are in control.
Then comes the test.
She goes out for drinks with someone else. She does something either major or minor, with other men. And this is when the "alpha" man, the fake it until you make it, I'm gonna practice playing with this one mentality comes crumbling to the ground. You say WTF? to her. You start behaving as if she is violating your trust or interest. She will blame you, saying you always seemed to never care about her because you are SO ALPHA and SPIN PLATES. She will take only partial blame, saying she started falling for you even though she knew not to. A man like you could NEVER be faithful! She did it because she doesn't want to be hurt, and figured you were just "having fun" anyway, being the so carefree alpha that you were.... you never showed me romance! You never bought me flowers!
That's not true, you will say. I'm not THAT cold! I did develop some feeling here, to be honest..... Sooner or later comes the romantic dinner.
Enter her DISAPPOINTMENT.
Disappointed you could not really live up to the FWB agreement without feelings creeping in. Or disappointed you changed your mind on the LTR thing.
It is not the beta she is disappointed by. It is the Alpha who was never really alpha to begin with. Her ego boost on controlling men does not come from controlling betas. It comes from breaking alphas.
If you're going to play along, you better be the real deal. Can you be ice cold when she comes on so warmly 3 months down the road? We shall see.....