I can assure you, when shit is broken in production and customers are knocking at the door threatening to cancel it is not a luxury to find out these types of things...let alone start untangling the web.
It's kind of a double edged sword- I've worked with a few people that "work hard" and "get things done", only to find out once they leave (or go on vacation) that now we have to untangle a 600 line bash script that's integral to production.
I'm being a bit hyperbolic here, but the gist of my point is: not everyone who works hard is worth keeping around, especially if their hard work leads to an un-managable mess in the future.