The brief and proposal
The first part of any design task is to identify the problem. The client may have identified the problem and presented it to you as a design brief. More likely, they haven't. Sure they may know they have a problem, but they don't quite know what it is and certainly don't know how to go about fixing it.
One scenario is that they think they want/need a Web site - but don't know why or what to expect of it. Even worse, is when they start suggesting solutions -when they haven't even understood the problem.