My mother used to say that if the our family was involved in a massive automobile accident no one would be able to call an ambulance, stop anyone from bleeding to death, pull anyone from a burning vehicle or move people out of the road until we had figured out whose fault it was.
This is a pattern you often see in families heavily invested in maintaining a Scapegoat. It's crucial to identify who is at fault in order to deflect blame from landing on you. Scapegoats and families which produce Scapegoats can be very hypercritical. They can also produce perfectionists.
Perfectionism can be a natural outcome of a blaming, hypercritical family system. If mistakes were not tolerated in your family it will be important to do everything in your power to avoid them. This may affect everyone in the family, not just the Scapegoat. It would seem natural that the Hero of the family would be a perfectionist, doing everything in their power to be "The Good One" and avoid being cast in the role of the "Problem Child". What is surprising is that the Scapegoat can also be a perfectionist, casting their own uncompromising, hypercritical glance toward their own behavior and using mistakes to castigate themselves. The family Scapegoat may use perfectionism to punish themselves, internalizing the punishing behavior of the family system.