I have spent a serious amount of time trying to decipher what that person did. What in the world were they thinking? Who thought that 13 nested if statements were a good idea? Who decided that five interlocking boolean conditions should go into the fourth nesting of those statements? Hadn’t they heard of an explaining variable? What the heck does the literal value 4 mean here? 9280 lines is a bit much for a single procedure, don’t you think?
So I shake my head, puzzle it out, and fix that bug. Or I wedge a new feature into that thousands-of-lines-of-code procedure. And I marvel that the code still runs, still (mostly) works, and still lives on.
Sure, we all laugh at the crazy stuff developers did back then. But it occurs to me that a little humility is in order. To our modern eye, which has the benefit of the wisdom of the past few decades, that code looks terrible. But maybe we just didn’t know any better back then.