We rate anything less than our best not good enough . The obsession with excellence is like a dog chasing its tail. It is a hike up an endless mountain. It's painful for perfectionists to make mistakes, yet we all make them. To err is human .
Perfectionists hate making mistakes.
They may believe they don't have the right to make mistakes, not even occasional ones with no serious harm done. That belief become a driving force of perfectionism. We don't learn if we don't make mistakes. We don't grow. They are afraid of making mistakes, which is a reasonable fear.