Another issue is that often effort is the only lever one has in providing value as what tasks you are assigned constrains potential value output.Hypothetically, If my boss assigns me a stupid project destined to failure and tells me to shut up when I push back I'm really not going to get much value regardless of how much effort I put in... unless I was wrong in my assesment which is admittedly possible. Good management I suppose would then use effort as a proxy to try to find projects with potential to match one's effort.