Know What Motivates You and What Distracts You
Having motives for doing tasks is like a prime mover which drives you to accomplish your tasks. Being motivated is necessary for everyone. You even have to motivate a child to encourage him or her to do something.
So make a list of things that motivate you and rouse you from your lethargy. For example, seeing a friend is a motivation for going to the sport club. In most cases, lack of motivation impedes doing a necessary task. You sometimes don't attend a meeting because it's your time to take a break, or you are tired of repeating those meetings and you no longer have a motive. In such cases, some happenings, like the presence of special individuals, can motivate you to attend.
Methods of motivating are different for various tasks and various people, so you can't apply the same formula for every task and every person. People find their peculiar motivational paths based on their own self-knowledge or intuition. Then create those motives for yourself when necessary.
Next, check and see what distracts you and stops you from concentrating on a task. Lack of concentration is one of the obstacles of time management. Make a list of items that reduce your concentration and contribute to you not accomplishing the scheduled tasks properly.
Just like the list of motives, this list is different for various people. Coming and going by others may distract you and make you lose your concentration, but the same thing may be quite unimportant for your colleague who can stay concentrated in crowded places.