When biking, swimming or running, but particularly when running, I will push to endure discomfort to make it to the goal I have set. If I am running with a friend, this becomes easier.
When working on anything else though, rarely do I have that much motivation. I resolve to approach the tasks I have to complete tonight the same way I do a run. there is a beginning and an end, and I don’t stop until I get to the end.