[asolove]

I think this is exactly his point. Most web projects start out immediately in project management crunch mode, listing long sets of features that are "priorities" for various use cases or stakeholders. In project thinking, lots of things can be priorities because you just do the first priority first and then you can add developers or time to do the other "priorities."

What needs to be obvious? makes clear that priority, from a design standpoint, is a fixed resource that time, money, and manpower can never buy more of. You want to add this feature and make it obvious, yes you can afford to do so, but no you cannot do it without making other things less obvious.