Template:Cyclic Trope
This is a Trope that goes through a circular pattern of change, eventually returning to its original form after several iterations.
Like this: "Fat Guys Are Jolly" gets subverted over time to "Fat Guys Are Kinda Sad And Pitiful". After a while at that value, the audience is expecting "sympathetic" Fat Guys, so it gets subverted to "Fat Guys Are Mean And Greedy". Once expectations are out there for evil Fat Guys, it gets subverted back to "Fat Guys Are Jolly".
Most cycles are bipolar, though, oscillating back and forth between two opposites that mutually subvert (or invert) each other.