Does it happen in your work? There are many different reasons for ending up with a pile of work that bores you. It's a chore that needs to be done and you have to get through it before you can get back to doing something that engages your full attention and feels productive.
There's lots of advice on how to tackle the mountain, from taking frequent breaks, to stressing out (a little stress is productive when the task doesn't require inventive thinking) to delegating the work to someone who will love it (there are some jobs no one loves). Over my years as a teacher facing a mountain of marking, I have tried most of the advice. It has all left me convinced that sometimes a chore requires a little mental toughness and a lot of persistence.
You don't have to love what you do all the time. You do need to nurture two very different parts of yourself. One part is the one who runs conscientiousness and duty and persistence. That part is habitually low maintenance but it does require fuel if it is to overcome a mountain. So think about who you are and what you need when you are persistent and honour that. You might need a treat or you might need to be a little scared. You might need to jump out and see the big picture. I don't know what you need, but you do. Think about it for a minute, and stock up if you're facing a big chore.
The other part of you that needs nurturing is the dreamer in you, the part of you that is the flip side of the realist who persists and takes responsibility. The dreamer in you needs your promise that this chore is only part of the story, that you will not lock her inside monotony forever. You might even welcome her when she pops in to interrupt the monotony and give your mind a change of pace. The dreamer knows that your real self in a perfect world would not be doing this chore and she looks for ways to inspire you with visions that will be quite helpful after you get past this mountain. Your heart beats more strongly for the dreamer, and your senses open.
If you're facing enough work for two people, allow yourself to be two people: the one who will plow through the chore and the one who lives in a bigger world where this mountain is just one step on a long and engaging journey.