Well, we have to fight that feeling, because for me, no matter how comfortable we are in doing our work, there are times when we feel bored and fed up. I have experienced this, where I felt bored and I thought about leaving my job at that time, even though at the beginning I was comfortable with that job. But luckily I was able to fight what was bothering me, and after that it returned to normal. That's why I say that there is a phase where we will feel bored.
Fighting this just requires identifying the real cause of the issues, which might be the environment that you are working in, the work load stress due to the work, which usually causes mental instability, and many other reasons. The first thing to consider is the reason so that you can tackle it without quitting your job because if you quit, no one will take your responsibility, so the best is just to find a solution.
Although this happens most of the time to people that are working to get paid, the real owners don’t feel that, so I am still confused. That is why I want to know why it is that the poor always give up easily and the rich hardly give up on what they want. I don’t want to use the word lazy because no one is lazy; it deals with destiny and wisdom. That is why I use the word give up.
From what I have experienced, this happens because of continuous habits or our activities at work every day are just that, causing boredom which in the end triggers us to think about things that we don't really need to think about, such as stopping work and so on. There are many ways to overcome this, such as taking time off and going on holiday, creating a new atmosphere ourselves and so on.
Once again, things like this can actually be fought if we can think with a cool head, because usually what makes things worse is when we think when we can't get our heads to think clearly.
However, this is a piece of advice, because the person who will make the decision will be ourselves. Don't let us regret the decisions we take later, that's what is dangerous in my opinion. Whatever happens, we must be able to think clearly, it is better to leave all activities when we feel something like that to make us fresher.