I feel the complete opposite. I structure projects, not my time. I want a loose schedule. You could stop worry about time, try a free schedule, enjoy life a little, and get work done. This whole "productivity" bullshit is an urban concept. Back when my grand pa was a farmer, he didn't have a schedule but he worked all day. The task can take as long it has to. I am willing to bet, your average urban wizbang with TODO apps and productivity hacks will not match the output.
I hate doing that so I work freelance, on a loose schedule. I still track my time so I can do things like “feel confident that I’m getting enough shit done fast enough to have money for rent”.
“Get shit I gotta do out of the way as efficiently as possible so I can do the stuff I wanna do at my own pace” is also a possible reason.