Yeah, I've had so many experiences of coming back to something I wrote 6-18mo ago, and being so relieved that I wrote it "simply" and with clear comments explaining the intent/purpose. Not only a great refresher, but anyone else could also gain context and easily make changes. I think there's also an aspect of that "broken windows" phenomenon[0] where inscrutable code existing in a project becomes a sort of implicit acceptance of more such inscrutable code being added to the project.
This is my biggest pet peeve of them all. I tell wet-behind-the-ears engineers "always strive to make the life of the next person to touch the code easier, even if only because the 'next person' will probably be you."