There is when much of the code was "write once, read never". There's more than a a few dozen MB blobs of dense perl5 code that we had no clue what it actually did, and was told not to touch it, lest many things break.

I had to end up touching one of them, because of things breaking with that subsystem and the new ticketing system that was being implemented. It had the wonderful line

     database_user = root
     database_password = [current mysql root password]

Lest to say, I no longer work there.