Having a potentially good system for Time Management is one thing but if do not have the self discipline to see it through then it is worthless.
There can be many reasons for poor self discipline:
Boredom is a bit harder to get to grips with. The reasons for boredom or lack of interest in what you are doing can be varied.
In the case of tiredness obvious solutions will be more sleep and not to take on too much work.
However, one of the benefits of good Time Management is to create better use of the available time. You will not feel so mentally exhausted.
Bad health can often be tackled by some sort of health regimen diet, training etc.
Many disciplines will become a habit if only you can stick at it long enough to make it into a routine.
To see anything through to the end requires a positive mindset.
If you can carry out a particular activity for a period of time it will become ingrained.
Try changing a habit for 4 weeks and by this time you will find it hard to go back to your old ways.
Make sure your daily tasks and weekly plan are visible. This will help you keep on track.
Set deadlinesMake sure you have a finishing time for all your tasks even if they are not passed downwards.
Break tasks into smaller stepsSometimes a task can seem rather daunting and you may find it very difficult to actually get started.
Force your self to begin but break the task down into smaller chunks. When you have completed each one you will feel much better for having completed something.
Make sure you plan well to give you the priority list from which you will be working. Check on progress against this plan and take corrective action as necessary.
RewardOnce you have completed a task reward your self in some fashion.