When I work with my clients on implementing a new software system, one of the first things I tell them is this:

“We will make some decisions that ultimately are wrong. Because things change. We’ll make the best decision we can make, given the information we have at the time, but we may find later on that it was the wrong decision to make. What’s most important to understand is that that’s OK. We can adjust and adapt, and everything will be fine.”

Acknowledging that things change during a project is critically important to the success of the project. If team members (and other stakeholders) believe that anything less than perfection is failure, they are guaranteed to fail. What’s most important is how the team responds and adapts to the changes in the project. And by acknowledging that changes will occur, you set yourself up for success rather than failure.