This is something we have been studying in my negotion/conflict resolution class. Is anybody familiar with it?
Basically it states that out of 100% of effort put forth, 20% of the effort leads to 80% of the outcome.
This seems to apply to many many different things:
20% of your carpet gets 80% of the wear.
20% of the population holds 80% of the wealth.
The list goes on and on.
Several books have been written about this theory, it’s pretty intersting I think.