This is completely contrary to my experience. A million lines of code in ANY language takes quite a bit of process to do successfully. I should know - I've written and managed 2.2M lines of code by myself. As for 10k lines of code (in any language) - that's quite easily handled by 1-4 programmers.
As for complexity of Perl applications - 90% of every Perl application you, personally, will ever really want to write is either already on CPAN or will be in the next year. So, really, you're only writing 10% of what you would have to write in any other language. Couple this with the 10-1 LOC difference between Perl and most other languages and my 10KLOC is your 1MLOC. All of a sudden, it's not so hard to manage 1MLOC.
My criteria for good software:
- Does it work?
- Can someone else come in, make a change, and be reasonably certain no bugs were introduced?