When I started my cave training I had no way of knowing who was a good instructor and who wasn't. I didn't know any cave divers. I'd found online forums, but didn't know any of the people there. I could ask around on forums -- no one will say anything in a public forum but some will via PM, but there's no way to judge the quality of those recommendations. So I ended up training with three different instructors (one of whom was a 'big name') and getting certifications from two different agencies (and I'm planning on some further training with a fourth instructor this spring). I'm more educated now as to agency and instructor and I know many more cave divers than I did then, but how's a newcomer supposed to choose wisely? If you ask about agency the answer is that agency doesn't matter, instructor does (although NWGD alluded to one agency being more stringent than the others, but not naming it -- I know the one I'd choose), and if you ask about instructor, well you may get some answers, but there's a lot of variability -- so many options these days.
Then there's following the rules. I suppose there are divers that follow every rule every time, but I haven't met many of them, and I've dove with a number of well respected divers. Sometimes blindly following a rule ignores the instances when following the rule might be more dangerous than not. Classic example is running a line down the ear at Ginnie when four training teams have already run loose lines down billowing in the flow and a fifth is trying to pull one. I guess it's possible that someone who's dove Ginnie a hundred times could still get lost between the end of the gold line and open water somehow, but the risk of somehow not just letting the flow blow you out to OW seems much less than trying to add another line to the existing rat's nest.
I hate the wrist-deep handprints in the clay and the broken rocks glaring white and the long grooves scored in the floor and shake my head at the stage bottles in the middle of the floor and the rebreather divers doing drills blocking the exit not making way for the exiting team and the guy on his knees in the silt futzing with his gear kicking up clouds of dust, but I'm no expert, I'm just a novice -- I do my best to be polite and cause no damage and my instructors at least paid lip service to respecting the environment and fellow divers. When there were only 10 cave divers in the world no one would act up; now that there are 10,000 (or however many there are) most of us are anonymous and there will be some rude folk in any group that big. Can try to blame training or instructor or agency, but it's human nature. Miss what is lost, respect what is left, and I'll try to keep my side of the street clean.