O-1B Deep Dive Part 5: Achievements from organizations, critics, government agencies or other recognized experts

One criterion for the O-1B requires evidence that the artist “has received significant recognition for achievements from organizations, critics, government agencies, or other recognized experts in the field in which the alien is engaged.

Such testimonials must be in a form which clearly indicates the author's authority, expertise, and knowledge of the alien's achievements.”

But what does this mean? What do you need to show to satisfy this criterion?

And why do so many people make mistakes in this area?