Time management is a weird enterprise. The more discipline, the more inflexibility. Things get done at the expense of other things.
Possibly, things of a more pressing matter. Not crisis mode stuff, but, important, relationship building, people stuff. The quadrant 2 stuff.
At the other spectrum is the no discipline approach. The world of stoners (not talking about you PHD having mofo's who smoke pot all day, you know who you are) and TV, and wine, and stupid meetings on top of meetings.
I like discipline. Sometimes it strangles your relationships though. Be careful not to worship your schedule.