How do you focus a person who does not want to be focused?

As a coach I find that oftentimes I am called on to "focus him/her".

And when I get there I think that what I need to do is quite different… help this creative individual see what happens to his great ideas when they seem to change every day or so?

Rather than try and focus this individual, the better strategy is in letting him run a bit in "moving the goal posts" just enough to feel that things do not seem to be moving ahead.

It is frustrating, I can guarantee you, but the opposite strategy- forcing focus- just puts you in a position where many others have been before: telling a wildly creative person that he or she must conform, do like the others, do their "homework" and so on…that is not going to help much, is it?

Any thoughts or comments on such a dilemma?