One of my favorite quotes on this topic comes from Aurelius' description of his adopted father in Meditations.

[Y]ou would never say of him that he "broke out a sweat": but everything was allotted its own time and thought, as by a man of leisure - his way was unhurried, organized, vigorous, consistent in all.

I feel like I spend a lot of time rushing from one thing to the next, constantly questioning whether I'm spending time wisely. And then I end up accomplishing less because I lack focus in one area. I've instead been trying to relax, slow down, and take tasks one at a time until completion. I'd also recommend Cal Newport's book, Deep Work, on this.