I'm finding a period of intense learning, on both sides, when a consultant and client begin work together. I'm not sure why this should come as a surprise -- what relationship doesn't include this?
But the rapidity with which the consulting relationship usually begins can obscure the reality that most of the time client and consultant don't know one another. We don't know how congruent our views are. We hope they're similar enough to make working together pretty easy. We hope they aren't so alike that the consultant brings no fresh perspective.
The client typically wants someone to take on the work to be done now, and the consultant typically wants to respond to the prospective client's sense of urgency. So there isn't a lot of time or room for deeper exploration beforehand.
Until the deal is sealed and both sides build rapport, there are other barriers. The client doesn't want to share every ugly detail of what might be at the root of an organizational problem and may or may not be objective about the part s/he plays in it. The consultant hopes the consultation plan matches what unfolds as s/he gathers more info after being hired, and that s/he's beem a good judge of the skills s/he can bring to bear.
Sometimes this works out just fine, but sometimes one side or the other is unpleasantly surprised by what's uncovered in the early days. I want to figure out how to make this more benign and more predictable, for myself and perhaps for the client as well.