As a reader, I never really understood why is it so common for textbooks to have the numbering à la
Lemma 9.6. To me it seems to imply that we also have
Lemma 9.5 and
Lemma 9.7 but sure enough,
9.5 is a definition and
9.7 is an example. So when I started writing my first big assignment, one the first things I googled was how to
But unlike the creators of TeX packages and most users of the TeX.SE, I know little to nothing about typesetting. So I assume that the default option wasn't chosen randomly and would be happy to know the reason and maybe become convinced that
Lemma 9.6 is the way to go.
Update: just to clarify, I meant why
as opposed to
So I'm not questioning the unified numbering (which it a good thing beyond any doubt).