That's body-language for "leave me the hell alone". Not everybody wants to talk or wants "help." ....
It can also mean None of you people have proven yourself to me yet. The trouble is that Dive-masters have just as much reason to be skeptical of the competency of their customers. There are horror stories on both sides.
I come from a world where tenders are paid to assist the diver in every way without getting in the way. It isnt that hard. Unlike tenders, Dive-masters are in the hospitality business. Like tenders, they should anticipate needs while remembering their job is to serve the needs of the diver. I think handing someone their fins, pointing out a dangling strap, or steadying them in a rolling sea is a common courtesy. Turning valves without permission or intimating they are somehow superior is obnoxious.
It takes time to earn respect on both sides of the ledger.