Would you expect someone who did their OW AOW in a quarry to go out and execute a dive in the ocean.
Yes. OW and AOW both, if their training has been what it should be. "OWD" stands for "
Open water diver", and a person who holds an OW or AOW isn't able to plan and execute a simple dive under benign conditions, then that person hasn't received the training s/he has paid for.
There are somethings you don't really have an understanding of until you really have to do it.
Sure. I've never dived a quarry, so I really don't have an understanding of it. However, my OW checkout dives were under conditions so benign that I have a hard time imagining it being any easier in a quarry. So, I started diving (non-guided) in conditions that are similar to or better than the conditions I was trained in and progressed slowly from there. There isn't something magical about "the ocean" that makes it inherently more difficult than a large outdoor pool (AKA a "quarry"), but there's of course a distinct possibility to encounter more difficult conditions like surge and/or current. I've called a number of dives even before splashing, especially in the start of my diving career, because I've deemed the conditions above my qualifications, that's just a part of the game.
IMNSHO, a diver who is issued an
Open Water cert, should be able to plan and execute a dive without being pampered and sheltered by a guide. Yes, for unfamiliar conditions a guide, or a mentor, or a more experienced dive buddy, is a very good thing, but the OW cert holder should be able to evaluate whether his skills are sufficient for the prevailing conditions, and to plan and execute a dive within his/her limits. As an added bonus, being able to plan and execute a dive oneself, often gives you the insight and self-confidence to evaluate the risks of and hopefully abstain from a dive like
this. Instead, those divers trusted the guide. With disastrous consequences.