Consistent deviations from the null hypothesis indicate the presence of a confounding variable and pave the way to new potential discoveries. A great example (a

Consistent deviations from the null hypothesis indicate the presence of a confounding variable and pave the way to new potential discoveries. A great example (albeit not statistical) is how planets deviate from their elliptical orbits and that this provides evidence for the gravitational pull of other hidden planets and moons. Having a simple model that gives you an expectation (usually the expected value E) can be extremely powerful.