How do we test hypotheses?
This is the counterintuitive part. This is the logic that seems backward. We try to disprove the Null Hypothesis. We try to disprove that nothing happened. If we disprove that nothing happened, then we conclude that SOMETHING HAPPENED.

Isn't that counterintuitive? To prove that we have an effect, that our treatment works, that our groups differ - we try to disprove that our treatment didn't work or that our groups don't differ.