Why is it that modern software development processes prefer stack ranking over priorisation? There is a simple answer – and isn’t (just) the simplistic “everything will be raised as a Priority 1” that you usually hear.
The fact is, there will be multiple Priority 1 (P1) items – and without stack ranking these, implicit decisions will be made about what to work on. If you have three P1 items and you can only deliver two this week, which one do you miss? There are many ways to answer the dilemma in this question – but unless you stack rank the cards everyone will use a different model to make the decision.
Stack ranking requires the model to be made explicit. It might be that you are driving decisions with economics, or using a simple model to select work based on rough data or estimates, or you might be using HiPPo-nomics where there highest paid person just says want they want next. The benefit of stack ranking is that the model is made visible to everyone and they can apply it when they are making decisions at all levels.
As soon as you allow many items to have the same level of priority, the models and methods of decision making become hidden and people will base their decisions on different criteria – meaning the decisions will not be consistent.