Tom Gillovich and Victoria Houston Medvech and Danny Kahneman were talking about in this 1998 paper. This now is called an adversarial collaboration. They argued that, quote, people regret actions more in the short term and inactions more in the long run because the sting of regrettable action diminishes relatively quickly,. whereas the pain of regrettable inaction lingers longer. And so what they did was the simplest possible set of studies to settle the debate.