Flakes happen to everybody. Get used to it. There are simply too many things going on in most attractive women’s lives to figure out why each one flakes. It could be because her ex-boyfriend started calling her again. It could be because she met her soul mate the day after she met you. It could be because she got in a freak accident and is in the hospital. It could be because she got sick and was bed-ridden. Sometimes women just don’t feel like dating for a while. Sometimes they don’tremember you well because they were drunk when they met you. Sometimes they lose their phone. Sometimes they just change their mind the next day.
And sometimes they just don’t care enough.
There are a million legitimate reasons women can flake other than then not being attracted to you. Trying to figure out which ones are flaking for legitimate reasons and which ones are not is more or less an impossible task. You’re better off just letting it go and moving on. In the end, it comes down to the fact that if she likes you enough, she’ll find a way to make it happen. If she's not finding a way to make it happen, then she probably doesn't like you as much as you thought she did.