They may be impressed but you may not have answered a question to their liking, or they found someone that has a better fit.

It sucks to hear it. I got countless thanks but no thanks emails and letters during my time when job hunting, but don't get stressed out and don't give up. You'll get someone that will truly want to hire you. Patience is the key.

Sounds really frustrating Karen, but I think employers are being honest with you. You have great qualifications, but it might be that someone else came along who was a better fit for the job. Keep at it, you'll find what you're looking for soon.