We spend a lot of time looking back at our past to either regret or miss something.
We miss childhood. We regret the stupid things that we have done. We rarely look back to learn.
Our past has so much to teach us. All the mistakes that we made were lessons in disguise.
What's better than failing at something and take home a lesson from the failure?
It gives us hands-on experience at what not to do in our future. Past is always a great teacher.
Take the famous trial-and-error method of solving a problem. We do stuff and keep iterating the process until we finally have an acceptable solution to our problem.
Why not make our life a whole trial-and-error experiment?
Take actions and see if they work or not.
When you're stuck at something, look back and try to find a situation where you failed at something related to your current problem.
You'll know at least one way how not to approach the problem at hand.
Learn from your past.