Another reason for failing to finish is that you are so unprepared for interruptions when one or more occur, you get thrown by it
Be open to trying new things and even fresh ideas or even new technology that might make it faster, easier , or better to finish what you started.
Make whatever you are procastinating about the very first activity that you tackle first thing in the morning, or when you first get to the office
If you have a fear of failure, you will delay finishing a project, so you do not have to deal with the potential negative feedback that you fear. If you fear success, procastination delays that scenario from happening.
If you the end whatever you are trying to finish at a good point, it will be that much easier to pick right up again when you can get back to it