There are people who start out learning many hours a day, and as time goes by they cannot learn as much, and they temporarily give up learning altogether, waiting for the day they will be able to go back to it.

This practice is very incorrect, first, because he has no promise that the day will come when he can learn more. Secondly, it is like someone who is about to faint from thirst and pours out the water offered him because it is not enough to completely quench his thirst. Although it is very commendable to learn for many hours straight, if one only has a few minutes he should utilize them to the maximum and not waste them.