It is difficult to start something new. It requires a lot of energy. And you may know that it is the same for continuing your work. But there is a difference between them.
What motivates you to begin a challenge is a strong emotion, or a belief. You may be fascinated in the words of your boss. You may fall in love after being struck by a passion. You may make a decision to do something because you have an ambition originating from deep inside.
These emotions are the source of startup. What makes you move is not logical thinking, but an emotion, even if it is sometimes irrational.
However, this kind of emotion will not be sustained. It is not easy to maintain a strong motivation for a single task for a long time. Your sweetheart will no longer attract you. Every emotion will be satiated, otherwise you would become sick.
So, what is important to keep your motivation long lasting?
Some people recommend you to go back to a beginner's spirit. They claim that remembering what state of mind you were in at first helps you to be enthusiastic recurrently. You would remind yourself that you have gotten some achievement with getting back in the spirit which you started, according to them.
Um, I am opposed to this opinion, although they make a point.
Most people who abandon something do not lose their motivation. It is not likely to quit working because of lack of dreams had in the past. Instead, they cannot keep working due to some barriers. Indeed, I had some conversations with colleagues who were going to leave. None of them said that their passion was extinguished.
They pointed out some tiny reasons why they could hardly continue working, such as relationship with their boss, infrastructure in working place, salary, and so on. It is the same in marriage. Some persons divorced suggested that they felt no more love with their spouse. But the reasons they told me are far from my understanding. Each factor is quite silly, however, accumulation of which is critical.
Maintaining a status is not equal to starting a new thing.
My recommendation is that you should resolve each issue which may bother you around the situation, no matter how it is little, if you truly want to keep the current position.