If you don’t manage your time, your time will manage you.
This quote makes me think of time as a headstrong animal, maybe a horse or a bull, that refuses to be tamed or trained. If you can’t control your horse, you’ll end up chasing it all over the field instead of riding it.
I suppose time is the same way. If you don’t take advantage of the time you have, you’ll be left wondering where it all went and why you thought there was so much of it to begin with. Time is stubborn in that way. It goes on whether you want it to or not, whether you’re spending it the way you truly want to or not. It doesn’t care about your regrets or your dreams or your intentions.
So instead of “managing” your time or “controlling” your time, I guess you can say that you “work with” your time or “make use” of it. It’s foolish to believe that you can manage or control what you really can’t, because time does not belong to us. We tried to categorize and organize it with instruments like clocks and calendars, but it still remains beyond our control. (Well, unless science fiction becomes reality and someone invents a device that can take us backward and forward in time.)
Sometimes you just have to compromise with time and go wherever it takes you, without lamenting that you should have spent that hour doing that “productive” thing. So it may be more about knowing when to jump on the back of time and go for a ride and when to let time gallop in the fields by itself.