Why do variables not reinitialize when script changed?

[Keith G. Murphy]

This is probably a very basic question, understood by everyone but...

Why, when I change a script loaded under Apache::Registry, and the
script (verifiably) reloads, do global variables not reinitialize?

I'm running Apache 1.3.9, mod_perl 1.21 on a Debian GNU/Linux system.

Am I the only one that finds it odd that the variables hang around
unchanged when the script that they pertain to is recompiled?

Perhaps this is stated or implied in the documentation; I didn't see it.