Many posts referred to this topic of earned-value, assuming that there had been an attempt at cohesion and closure. Well, no such post exists (yet), so the below will fill in the blank.
For starters, anytime that we plan a future activity (where the timeframe can be from the next minute to much longer), we have expectations and then the actual reality. Well, these don't always line up after the fact. Many times, hype tries to fill the gap as the expected value does not add up.
It's true, too, for serious things, like engineering, though, in that case, the gap or disparity is not as great as we see with economics (dismal science) , finance (ah, let's count the ways), medicine (unfortunately).
So, 'earned value' is a way to attempt to map results to plan to do things like check status of a project. Think of it this way. If one is doing a task and thinks one is 50% complete, what does this mean? Well, that estimate could apply to the steps in the process, amount of resources (or even dollars) used, the state of what's being produced or accomplished, and other things. Tying these things down is not as easy as it may seem.
How do we know? Well, Microsoft could tell us a lot, as could a few manufactures of complicated systems. Many other examples abound. In short, many feel that the problem is not solvable in the contexts allowed now. We really need a better way to think of these things.
So, let's get the hole in the blogs filled, or at least outlined, so that future discussions can refer back and extend the topic, and used 'earned value' as the label.
09/02/2009 -- Lets face it, folks, undecidability needs to be discussed and adopted in any complex situational setting, especially if computers are involved. Only hubris pushes us to make loud exclamations about what we're going to do in the future.
07/14/2009 -- Nope, confounding continues.
05/18/2009 -- Testing in flight is within sight.
01/26/2009 -- 'Earned Value' is used generally. Perhaps, one might argue for a more general term which may come about at some point. In the meantime, we'll continue to use that tag.