We did some diving in Bermuda with a small dive shop. I did 3 dives with them, the first 2 were with a DM that I quite liked and was friendly and would give you a decent (although still too short) briefing about the dive site before you entered the water.
the third dive was a much different story though. There was a new DM on the boat in the afternoon and he just said "This is a site with some tunnels. I will be going through them and dont have time to check on you, so buddy up and do your own thing..."
I was by myself that dive, so I had to buddy with another person on the boat that I didnt know at all, which is a little nerve wracking anyway. So we entered the water and we started to follow the people through the tunnels (most were just big rocks with swimmable holes). no big deal so far. I am just following my "buddy" at this point and am not familiar with the site at all. finally we start going through another tunnel and this time is is starting to get dark. On one tunnel its almost pitch black at one point, but I can still make out my buddy in front of me and I see the light on the other side. Its starting to get narrow too, so I didnt even have room to turn around. Im getting a little nervous at this point, but I figure I better stick with my buddy and keep moving forward.
Finally the tunnel starts getting quite narrow and I am worried about getting through (Im the biggest guy on the boat, so if anyone is going to have a problem getting stuck it is me!). At one point I have to squeeze through the rocks with them scraping on both sides of my body and I get the hose going to my gauges caught on something. Im now stuck... This is where I would normally signal my buddy that I have a problem, only he is no where to be found. We are almost out of the tunnels at this point so it is quite light again, but he just kept swimming.
I only had about 10 dives under my belt at this point, but I remained calm. Figure out what is stuck... dont try to force myself through (might damage something). slowly wiggle through until I am free... I was probably only stuck for a minute or two, but of course it felt like a LOT longer than that... finally I found my "buddy" and signaled that we need to stop with the tunnels, which he seemed to agree.
It was not until later when I dove with some MUCH better dive operations that showed me what a real dive briefing should be and how a DM is supposed to take care of the divers.
Most people complain about having to carry their gear, which is inconvenient, but having a DM not prepare you for the site and then not check on you at all is inexcusable and quite dangerous, especially when a site like this really should be reserved for more experienced divers.
Later when I checked online did I see that they had a LOT of bad reviews for similar issues.
Lesson learned... check on a dive operator BEFORE you go diving with them...