How to treat constellation brightness number _ constellation brightness number?

How are the α β γ stars in the constellation arranged? What's the point? ! ! !

Bayer (German astronomer) star naming rules: the stars in each constellation are arranged in the order from light to dark, and are represented by the name of the constellation plus a Greek letter. Later, those with more than 24 letters were numbered with constellation names and numbers. Most of them are arranged by brightness. Alpha star is usually the brightest star in the constellation, and so on, but there are some exceptions.