I think this is the quote that lead me to the book

Wherever perfectionism is driving, shame is riding shotgun. Perfectionism is not about healthy striving, which you see all the time in successful leaders, it's not about trying to set goals and being the best we can be, perfectionism is basically a cognitive behavioral process that says if I look perfect, work perfect, and do everything perfectly, I can avoid shame, ridicule, and criticism. It's a defense mechanism.

When I interview leaders, artists, coaches, or athletes who are very successful, they never talk about perfectionism as being a vehicle for success. What they talk about is that perfectionism is a huge trigger, one they have to be aware of all the time, because it gets in the way of getting work done.
It was from a business article called "WHY DOING AWESOME WORK MEANS MAKING YOURSELF VULNERABLE" but I think it translates.