Oliver Burkeman, Four Thousand Weeks

It follows from all this then, that spending at least some of your leisure time “wastefully”, focused solely on the pleasure of the experience, is the only way not to waste it – to truly be at leisure, rather than covertly engaged in future-focused self improvement. In order to fully inhabit the only life you get, you have to refrain from using every spare hour for personal growth. Take up a hobby, with no particular expectation of improving at it (and certainly not of turning it into a marketable “side hustle”). Go for an aimless walk. Stare out the window.

Oliver Burkeman, Four Thousand Weeks