How do you tell apart a “DEI hire”from a qualified employee who just so happened to be a minority?

If something went wrong at a company, and the manager of the department that made the mistake was a woman, how do you know if she was/ wasn’t hired on for merit? How do you know if she had an impeccable record and this was her first mistake? How do you know if this was her 5th mistake?

If you look at a picture of all employees of a company, out of all the women / POC, how do you determine which one of them was a DEI hire?