A question that has helped point to better product design every time I remember to ask it – what is the experience 80% of the users would want to go through?
When asked, that question first reminds us that we must let go of all the complexity we are likely to introduce as super-users of our own products.
It then pushes us to simplify our flows to the few things most users care by removing any detailed how-to notes, unnecessary choices/steps, and excessive copy.
And, out of this exercise emerges a principle that applies just as well to product or process design as it does to effective communication – focus on clarity over completeness.