If you want to find out what prospective employers think of you, don't wait till you don't get a job and then ask the recruiter for feedback. It's a litigious society, so they won't share it. The recruiter will say something generic like how much they liked you but the field was just so competitive. Furthermore, at this point, you are already closed out for the job. You can't use any feedback you do get because your next interviews will be for different jobs with different players. Instead of generic feedback received too late, you need to get personal and specific feedback that you can act upon before a decision is made. In order to do that, ask your interviewer these tough questions.