It really depends on the edition and campaign. My original campaign (1E) was always level 1, but everyone had multiple characters, keeping a fair balance among the group. My college 2E group used the lowest PCs total XP, since levels were class dependent. A 3E group I played with used level -1, because that was the punishment for Raise Dead (3E), and while they never saw an issue with it, I know 2 players who quit that game due to the death spiral (each new character was 1 level lower, leading to near instant death). I honestly don't recall any 4E deaths that weren't cut scenes or TPKs. My current 5E group has everyone be the same level, so new characters are the same. I've had a West Marches style game with this group, however, where everyone started at level 1.