Motivation to do all the things we want to do in life is often very hard to obtain. Sometimes external factors help us obtain the motivation, but it would be much more convenient if the motivation came purely from within. Doing research and not having many external factors like tests or homework assignments can vastly slow down progress and significantly reduce effort. Ultimately, if you are doing the things you really want to do, motivation should not be too hard, but even then, it can be.
As an example, I am taking a programming class and learning many things I legitimately really want to learn. Yet, every time we have an assignment I dread starting on it. However, the fact that I am getting a grade and have due dates for the assignments forces me to start. Once started, I usually thoroughly enjoy the assignments. However, the external motivation of the class is essential to make me work on the project and ultimately obtain flow from the challenge of the assignment. I surely would not have learned as much as I have in such a quick time without the course.
It is easy to be motivated to work when external factors are involved and the work is consistent with your overall goals. However, when there are no external factors it becomes much tougher. For example, I told myself I would finish writing a paper on my research by the end of the week and gave myself two weeks to accomplish it. I actually finished it in just over one week, which helps to explain part of the problem. It is extremely difficult to assess the challenge and time frame associated with self-imposed goals. Therefore, you really have no idea when to set the deadline. I finished my paper in about 10 days but actually could have easily finished it within 7. However, if I had vastly underestimated the difficulty of my task, I would not have met my goal. But what would have been the consequence? Nothing. I think this is why a lot of people recommend people make their goals public so that if they do not complete them, they suffer the embarrassment, but I do not think I am too affected by embarrassment.
I am really not sure what the solution is to keep one motivated. It certainly helps to be working on things you care about, but even then, I find myself working at a prodding pace without the external motivation factors. Certainly a coherent incentive environment would be valuable for this situation but this type of environment will not always be available.
Another thing I have noticed about motivation, at least for me personally, is the motivation to do something physical like exercising is much easier to do than something mental like programming or something social like going to a bar. Perhaps this is something I have just trained my body to crave. Nonetheless, I can always make it to the gym to exercise. It is obviously much more mindless than doing mental work or being social and perhaps this is the draw of it. I am curious to see if any studies have been done to see how people's motivation change to do physical or mental work as well as the motivation to be social. The explanation may just be that I really have trained myself and have forgotten the pain period when I was first getting started. Maybe it really is possible to make a schedule for doing intense work, exercise, and socializing. However, it is just too easy to ignore any of these things. There has to be a way to make it easier. Any ideas?