Look back if you can.
Learn from all your past mistakes;
Then change your future.
Many people live in the past. They wallow in the misery of past mistakes. Yet, we cannot change the past. It’s gone. Would you aim to empty your trash bin, to recover the contents for sentimentality’s sake? Of course not. Once it’s gone, it’s gone.
Still, let’s say that you threw a favourite china cup in the trash because it was broken. Now you can do something: You can learn from the mistake that broke that treasured possession and try to ensure that it doesn’t happen, again, with the replacement.
In the same way, leave past mistakes in the past; but learn the lesson, and change the future.