Why do mistakes = failure? The word miss-take. Means you just found the way of doing something that didn't get you the results you desired. Post-it note glue was a mistake it went wrong. Still they came up with something that had a different use than what was intended. Without the mistake the company would lose out on a huge market. If wasn't a failure it's just something that produced the unexpected.
There really is no such thing as failure. It's all hidden behind a decision why you chose to create a mistake rather than head down the path you thought you should.
I've made the mistake of taking the wrong turn yesterday and later found out I missed getting stuck behind a clean up.
There is good in mistakes.
Alex