An assumption is essentially an unanswered question. Answer them early and often during the course of any effort and the risk of failure plummets. In addition, the risk of starting something doomed from the beginning is minimized.
Despite saving huge amounts of effort, resources, and money, don't expect a stress-free ride down the Assumption Trail. Many people react strongly when their assumptions are questioned. It's tense.
Posted by: William W. (Woody) Williams