We believe the simplest the better, but still try to be descriptive as possible and use pictures when needed as a better way for conveying your idea to us. By doing so, you oblige yourself for a more detailed project definition and invest more thought into it. The better the project definition is, the easier it is to implement it, and the more satisfied both sides are.

If you want to have an idea of how the communication works regarding simple projects, have a look at The Amazing Escape example.

If you want a live example of a very big and complex project, have a look at ProFindler.