Diminishing Returns

Diminishing returns happen when resource (time, effort, money, space) yields less output than it did at an earlier time.

In math jargon, diminishing returns happen when the productivity curve starts to flatten out.

Diminishing returns are essentially the inverse of the Pareto 80/20 Principle. Once the 80% of gains are made with 20% of the effort, what are you left with? The final 20% percent of the improvements will take many times more effort than the first 80% percent did.

NOTE: This is not an absolute rule. Sometimes, even though a small number of factors are causing the lion’s share of the problems, the effort to fix those few items can be enormous. In the vast majority of cases, though, the critical few causes offer a bigger bang for buck than the trivial many.