Earlier quoted context omitted.
Just to add that some BASIC dialects had a RENUMBER or RENUM command that would change all line numbers and references to use a consistent interval. Without that, programs could become hard to modify due to the "gaps" between the lines closing-up.
Couldn't you just increment by 100? Or even 1000? Why did everyone use 10? Was it some interpreter limit that didn't allow line numbers above a certain amount (like 2^15 on a 16-bit CPU)?
You can get around that with some flags, but its more of a pain than its worth.
We tend to go by hundreds for programs, and we have a renumber command, but using it is the nuclear option because it will break goto line number references from outside programs (yeah, that's a very common thing in this language)