Used in sports to explain why teams who win championships are often ultimately dethroned, not by other, better teams, but by forces from within the organization itself. The players want more: more money, more TV commercials, more playing time, more media attention, etc. As a result, what was once a cohesive group begins to fray and they end up failing.

It's the constant chasing of pleasure. 

People who are constantly striving for a “better life” end up expending a ton of effort only to end up in the same place.