"You've got to be very careful if you don't know where you're going, because you might not get there." - Yogi Berra
When you hear the suggestion that estimating is somehow of little or no value to the project, ask do you know what done looks like in units of measure meaningful to the decision maker? Yes, what are that units.
- Value Delivered - these are the capabilities provided by the project usually stated in Measures of Effectiveness. These are operational measures of success that are closely related to the achievements of the mission or operational objectives evaluated in the operational environment, under a specific set of conditions.
- Cost and Schedule - these are the targets provided by those supplying the money for the project. While there is aversion to sticking to the cost and schedule, those funding the project probably want you to make an attempt to do so.
- Performance - these come in two types. Measures of Performance, which characterize physical or functional attributes relating to the system operation, measured or estimated under specific conditions. These are targets like all the measures, for the performance of the results of the project. Key Performance Parameters represent the capabilities and characteristics so significant that failure to meet them can be cause for reevaluation, reassessing, or termination of the program. And Technical Performance Measures are the attributes that determine how well a system or system element is satisfying or expected to satisfy a technical requirement or goal.