Magic Forums

I have been reading some of the forums posted here by "covens" and I am fairly amused by it. I suppose the problem is that I do not understand how covens were started and why so many have just appeared and who decides who is knowledgeable enough to be the High Priest and High Priestess? Who decides if the ones in charge of the coven have the knowledge to advise and teach the coven? i have, in the past tried several covens and left each one as they have been true disappointments. Perhaps if someone would e so kind as to share a response or thought with me...I would appreciate it. There is no true disrespect intended just a few honest questions.