There could be multiple reasons why. My top 3 are:

1. She spoke to you on the phone and there was no chemistry for her yet she continued talking to you just to be sure that there was no chemistry

2. She spoke to you on the phone and you came on a little too strong and scared her off

3. She has someone in her life and decided she does not want to step out on them with you

Not all women are flakes. Some women say they want honest "real" men and they mean that. You may happen to be a good and honest man, but does that mean she should automatically want to be with you because you are those things? When it's all stripped and bare you need that chemistry...