Basketball players often ask me how many hours per day I practice or have practiced in the past, at their ages or in college etc. I never give a number, for two reasons:

Many people will take one piece of what someone did and think if they copy just this one part they can replicate their success. Wrong. Success and failure are rarely that simple to explain or model. Athletes would take any number I give and then think they can __________ (achievement) if they do the same amount or more, which is also wrong.
There is more to succeeding than just the convenient parts to copy; you have to do everything that person did, even the stuff you don't like. Many don't want to do the dirty work, only the pretty work. This is a recipe for failure, discussed here in detail.

If you're watching the clock in anything you do in which you don't have any time constraints, you're doing the wrong thing. You're only doing it

to say you did for _______ (time amount) as an achievement
to get it over with and appease yourself or someone else
for a reason you don't even know or can identify


All 3 are reasons to stop doing it. Or at least start figuring how to get out of it. Knowing you want out is Step 1.