Failure is great. You read that right. Yes, it is no fun at the time, but it can be fun. It's productive, progressive, and like a "superfood" it's packed with lots of goodies that are good for you.
I define failure as having tried something, but the intended achievement just didn't quite happen. This is similar to experimentation. It is, too, a component of competing. Failure is equivalent to not acing the test. Heck, even scoring 100% (for all of you students who read this blog), there was failure involved in reaching that amazing, perfect mark.
In my book, failure is positive - more than that, in fact.
Failure has an evil twin.
Mistake
I define mistake as carelessness. That simple. The connotation is not putting forth best effort. Cheating the design, bending rules, and taking advantage of others' efforts to achieve fit into this category.
So what's the takeaway?
Go and fail.
That means you're trying. Maybe it didn't work out; maybe it won't work out. Good faith and effort was or will be there. You'll inevitably learn something along the way. And, mistakes may be reconstituted into failure if compassionately, honestly, and openly acknowledged. No one is perfect.
The themes here are trying and learning.
And that's why failure is great.