There is a well-known Buddhist parable about a man and a raft. I'll try to paraphrase it:
There was a man who was on a journey somewhere. He was travelling through a forest. He came across a great river in his path. In order to cross it, he began to gather together materials from the forest and constructed a raft. The man was able to cross the river using this raft. On the other side, he stood admiring his creation and its success. He wondered about what to do with the raft now that he had crossed the river. He was proud of its craftsmanship and its beauty, so he decided to carry it with him. Weighed down by the raft, he was never able to complete his journey and died in the forest.
I'm not sure if I've retold the story properly, but this is how I remember it at least. I think its usually told as a way to understand various Buddhist 'techniques' and 'practices' for attaining enlightenment. Once you've reached 'enlightenment', you can then leave those techniques behind, like the man should have left the raft behind.
I usually think of this story when thinking about my 'achievements' or 'failures'. Especially in the case of 'achievements' though. If we become too attached to our achievements, we become weighed down and defined by them. It is much lighter to leave them behind and move happily to the next thing.
I find that learning to let go of my 'achievements' is good practice for also letting go of my failures.