I tried to join a Coven in freshmen year of High School because I was a stupid high schooler and wanted to be magical and also maybe have friends?
I was kicked out halfway through the first meeting for "messing up all their spells".
The reputation has followed me even to my current software job, where I am often giving things simply to use, because if it's working by some sort of dark code magic instead of working correctly, it will cease to work at all when I'm in front of the machine, so I am a convenient way to test.
This is typical of tech workers. Bugs only occur when there is nobody around to help.
I find that the presence of even the moderately skeptic can cause even the most powerful magician to suddenly feel that he's "not strong today", as Uri Geller repeatedly told Randi and Carson. Remember that a prize of 1 million dollars was offered by the Amazing Randi for the performance, under laboratory conditions, of any supernatural powers whatsoever and not one person ever was able to pass the tests. Many tried, and many were even
shocked that their powers weren't working. People can even fool themselves if they believe hard enough that they can do magic.
And yes, the psychic was able to work hand in hand with the foundation to create the testing procedure. And they would accommodate requests like having Randi leave the building etc. so the psychic could work uninterrupted. And you could even turn down the prize if you wanted, which meant the old chestnut of "I can't use it for personal gain" is meaningless. Besides, Sylvia Brown sure profited despite her numerous failures and only occasional, peripherally-successful "hits".