Freedom is a curse. Tbh we humans are wired to seek order and structure. As someone that has lived through chaotic free no-routines life and felt like shit, for me personally, I NEED order in life.
Also, you can be perfectly happy without self-improvement or routines. Many are. But for some, it becomes a necessity.
For me, self-improvement is the ONLY antidote to depression. It is what inflames my soul and excites me every single day.
But again, you MIGHT not need it, not everyone does. It's all about what you find meaning in