The projects I've enjoyed the most is where I felt I was building something meaningful, as in something I believed would help the company grow. And asking questions that challenged the point of specific thing was encouraged - when I voiced concerns that RoI isn't there, it was at least considered and sometimes changed the plan. I don't expect my suggestions to be right, because I see only part of the picture, but I assume so does upper management, leadership, etc. It's just impossible to grasp the entire thing. Like you can't be just dev and not think about how customers will be using what you release. For me working like that feels more fulfilling and I like to think it helps to mend these perspectives.
On the contrary, worst time I had was when I was just receiving roadmaps to crunch through, that were "set in stone", came from "up there" and suggestions or personal findings weren't part of development. Yes, the technical challenge was there but that alone doesn't cut it. So it felt like I'm just a cog in a machine and after some time the mood just drops and burnout starts creeping in... I find it very consistent.