Failed ideas or products do not make you a failed entrepreneur.

If you look back on every failure and can honestly say (a) I didn't repeat the mistakes of the last effort and (b) I am learning what to do for next time, then you are probably on the right track. Though this is the naive, altruistic view of things. But sometimes people need to be reminded.

The problem arises when people aren't being just absolutely brutally honest with themselves. It's not just execution that needs to be fixed, sometimes it's the people or it maybe the market doesn't truly exist.