I'm going to stick my neck out here....
My experience suggests that two-thirds of aircraft engineers couldn't hold down a job at the local automotive main dealer, or worse; the other third is wonderful! Because of the restrictions and the difficulty of removing an aircraft, the unscrupulous majority can (and do) hold the owner to ransom. Rip-off is the name of the game. The owner has no sanction. Many is the time I have known I could be doing a better job myself than the bent idiot with the spanner, but I'm not qualified? So can you blame anyone who feels capable, really? I've known PFA'ers with a permit aircraft who could outshine many a LAME and some who are abysmal. The CAA created this scenario; they need to sort it out.

Rant fading....