[valuegram]

"We noticed early in the Stack Overflow beta that users desperately wanted to reply to each other, and were cluttering up the system with "answers" that were, well, not answers to the question. Rather than chastize them for doing it wrong – stupid users! – we added the commenting system to give them a method of annotating answers and questions for clarifications, updates, and improvements."

This is excellent advice not just for online ventures, but for business in general. Too much time is spent making rules and regulations to prevent customers from taking certain actions, when a lot more can be gained by understanding what your customers are trying to do naturally, and finding a way to support that.