Milestones alone are often abused, too. In startup work, people are invested and there's too little time and even less reward to compare what I'm dong to what

Milestones alone are often abused, too. In startup work, people are invested and there's too little time and even less reward to compare what I'm dong to what someone else isn't. If someone doesn't deliver, someone else steps up and we move on. In mature organizations, everyone is not running to the copier, and people begin to take notice of the terrain. Politics, unpredictability, and general people challenges are perceived as a drag on the system. As a defense mechanism, especially if incentives are involved, milestones are defined not for the common good, but to route around points of potential failure. Milestones make it really easy for the offense to blame special teams and the defense to blame the coach after the team lost, even though they all celebrated success at different times during the game. I agree, progress and outcome is what counts. And I think iteration and feedback loops are essential: yesterday's unrefined solution isn't the best answer tomorrow.