Can't start with dialogue...should start with dialogue...should start someplace exotic, like Panama...should start someplace safe, like Montana.... There's a rule for everything.
Some very successful writers break the rules with impunity and do it wonderfully well. M.C. Beaton head-hops like a dervish--she doesn't stick to just primary characters, either. She'll hop into some passers-by head at will. And I have read all of her books, some repeatedly. She uses wonderful characters to tell stories I love to read.
Janet Evanovich has a big info-dump at the beginning of every Stephanie Plum story. She makes it work. I love Stephanie and I have all of her books. (Even the first, scary one, which I won't read again.)
Carl Hiassen does a biography for almost all of his primary characters--and there can be a dozen of them--as he introduces them. This can take a few paragraphs or a few pages. If you're Carl Hiassen, no twelve-year-old (New York) editor is going to tell him that he can't do that. As a reader I relish his rule-breaking and read every word.
No head-hopping. No info dumps, no piles of excess backstory. HUGE rules that are like commandments for writers.
I guess the moral of the story is that if you're a best-selling author (who writes incredible stories that grab you and pull you into their world and won't let you go until the last word) then you can break the rules with impunity.
As long as you do it well, the rules don't apply to you.