I’ve never once seen “come back and fix with deadline” work. It’s really only the “with deadline” that does not work. Good teams will constantly be judging if now is the right time to fix the thing, and that fluid process works pretty well. Setting deadlines for tech debt just leads to the people setting the deadlines getting upset and quitting when they are inevitably missed. Save the urgency for when it’s warranted, like discovering a time bomb in the code, a scaling limit that is about to be breached— people will take you more seriously, you will be happier, they will be happier, hooray.

By all means, shoot for absolute perfection on your own projects. I work very, VERY differently on my own code than I do on work code, and I get different types of satisfaction out of both (though of course massively prefer working solo).