The original intention of the option
unclear what you're asking is obvious.
Nevertheless, every now and then there are questions in the closing queue that are actually clear enough, but end up receiving close votes as "unclear".
Is $Tds=dh-dp/\rho $ a valid definition for entropy? has been put on hold as unclear, but it's only missing definitions of the symbols, which are actually rather standard.
First law of themodynamics asks about energy per d.o.f. ($k_BT$) and heat ($Q=mc\Delta T$): whether equivalent and when to use. The question, put on hold for being unclear, is actually understandable.
The physics behind Basin structure has a crystal clear, if trivial question (3 "unclear" votes):
Why are such holes [in a sink] kept and why is not a large gap produced so that water runs out?
What these questions have in common, it seems to me, is that they show a remarkable sloppiness or a remarkably broad misunderstanding.
While the last example might rather be off-topic/engineering, and the first two probably could be off-topic/lack-of-effort, I think that voting "unclear", by requesting the OP to elaborate, delivers more clearly the message that the OP should get his concepts sorted out.
I'm sorry if it's too much hair-splitting, but my question is: Is this practice fine?