Why can't you repay the debt by just rewriting the code instead of refactoring it? I once paid off a technical debt incurred by a previous programmer who had d

Why can't you repay the debt by just rewriting the code instead of refactoring it? I once paid off a technical debt incurred by a previous programmer who had done a code and dash of epic proportions. The code was utterly horrendous, and so many changes had been done in-place, right on the production server, with hard coded paths, that we had to rewrite it bit by bit. We didn't even know all the functionality in it, other than that it was in active use (we found and interviewed people to get a full sense of what it did). It took years, but we did pay it off.