Third Bear Claim
In the Goldilocks and the Three Bears story, Goldilocks tries things in threes: porridge, chairs, and beds. She always finds the third thing just right: the first thing being wrong in one direction, and the second in the other direction, with the third being just right.
People often talk about their own choices in this way. The most famous is probably that drivers think everyone faster is reckless and everyone slower is incompetent. Another famous one is the Blub Paradox. But these are quite common everywhere.
I've wanted to refer to this idea of there being some continuous parameter along which people are placed in some respect, and where they will claim that they are at a critical point for some function of that parameter irrespective of what the fact is. There isn't a convenient term and the Goldilocks effect does not refer to the specific idea that the claim is made without reference to evidence.
Therefore, I shall call this a Third Bear Claim and the property that people routinely make Third Bear Claims shall be referred to by me as the Third Bear Effect.