Over the last few years after seeing hundreds of projects come through my company – if I have learned one thing – it is that defining the problem is half the battle.
So many times people will send over “documentation” which can sometimes be in the form of a mockup, an email, or a full blown specifications document. Most of the time the most difficult part of the project is extracting exactly what the client is looking for and not how to properly implement it. The client might even write one thing and actually mean something else so I always make sure to have the client clearly define what it is that they want. If they cannot clearly define something – how can you define the project or even the project’s success?
All I can recommend is that before getting into a project – make sure the client can clearly (in writing) state what they want as well as how to test it (you may need to help them a little). By having both the client define what it is that they want and how we can test it (to meet the end goal) – you can then reference the what and show them the how – using their own words thus showing them they got exactly what they originally wanted.
Above all…documentation is king.