I guess you know the situation, that with some of your colleagues you manage to establish a common way of communication right away (whatever you talk about is understood perfectly by the other one), whereas with others it takes a while or maybe never gets established.
I understand that to a large extent that's related to communication skills in general, but I think it is particularly important when you as a project manager assign tasks. You explain the overall objective, how this fits into the overall project, within which time the results are expected, maybe give indications how you think this can be solved, and your colleague agrees and indicates everything was well understood (which may or may not be true).
What seems to me very important in that regard, is that just because of fear of not being understood to start micro-managing.
So which possibilities come to your mind how to make sure that you managed to express yourself understandably? How do you deal with people that, for whatever reasons, would not come back with questions for clarification to you and rather spend a day or even week on something that does not contribute to the overall progress?