I got into this career because I like mucking about with this kind of work. Programming is sort of like building thought sculptures. Ok, maintaining them too. I spend a lot of my adult life working with these systems, so of course I care about their quality.
It is unpleasant to work on a hack-filled creaking monstrosity of a codebase. My skills, such as they are, don't help as much as it feels they should, because I rely heavily on understanding a system based on how it sort of has to work given what I know about the constraints, and hacky systems constantly confound my expectations. That means I have to spend way too much time and effort learning the idiosyncrasies and unpredictable corner cases, and so have less time to make the changes I want to make. It's like a carpenter working on a house where nothing is straight, nothing is level. Or a cook given flavorless or half-rotten ingredients to use. You spend more time picking out the bad (or picking out the good and discarding the rest) than actually cooking.
Any my scope is limited. Some changes are just not feasible to make, because there are too many hidden and/or unnecessary dependencies buried in the code. If you change one thing, everything falls apart. If you patch it together well enough to more or less work, you're faced with a long tail of subtle bugs that you'll be battling for a long time to come. There's no conceptual integrity.
Furthermore, working with a team that accepts a never-ending accumulation of creeping technical debt is also unpleasant. You can't trust that a positive review means anything. If you try to do something right and take pride in your work, your teammates will be resentful that you're not closing your bugs fast enough. Who cares that it means less maintenance overhead in the future if nobody's planning on sticking around, or people are depending on things being constantly broken so that they can spend their days knocking off relatively easy whack-a-mole style bugs?
Bad code is actually fine. It happens. But I want to know why the code is bad, whether the reasons are defensible or not. If they aren't, I know that the codebase is going to be littered with similar crap, and that my job is going to suck. That's what bothers me so much. This is true even if I'm the author of the bad code. Why didn't the reviewer point it out? Is it like the article said, and there's nobody competent enough to spot glaring issues? That is also a component of a job that sucks.