people sometimes say that creativity is born from constraints.
one form constraints can take is in the constraints that arise from writing serially and having to maintain consistency with your previous chapters. I DO believe in going back to edit stuff when it's absolutely necessary, but this still has to be done within reason. While it can be frustrating to be stuck with the elements you've set up, there's something to be said for trying to make do with what you have.
For example, (minor spoilers) in Chains of a Time Loop chapter 53, I was originally stuck when I realized that there would obviously be some kind of guard staking out the location the characters were trying to get into. This stumped me for a while, but I eventually realized I could pull together a reasonable heist plan based on a feature of the location that had been set up earlier in Book 1. I had fun writing that bit, and it led to me finding more ways to incorporate that element into the story, which is for the better.
constraints can also be imposed more intentionally. in my other WIP, which is not a serial work, but something which will get the full edit treatment before being posted, I have a setting where the supernatural elements are a lot more narrowly defined. There isn't quite as much wiggle room to pull spells or artifacts out of my ass whenever I need to, not even with the ability to set things up arbitrarily far in advance. This is obviously due to my own choices with the setting, rather than a hard constraint of causality, but nonetheless, sticking to these constraints forced me to think outside of the box, and again, I think this has worked out for the better.
All that said, I think I would hate to write a work that's both written serially and has a hard magic system. That would be too many constraints for me.
(Yes, I do realize it probably says something about me that I consider COATL to be the soft magic system here.)