The end of the year is always an exciting time. It's a time for reflection over the past year, and anticipation for the upcoming year. It's full of dreaming, planning, goal setting, and list making.

Lots of goals and lists it turns out.

That's because we see successful people and the many things they seem to get done. We then interpret their ability to get so many things done as multitasking. So, in turn, we do what we think they do: We load up our year with goals and lists.

There is some science behind why we do this. Multitasking makes us feel good, according to Zhen Wang of Ohio State University. It makes us feel satisfied because we think we're accomplishing more, even when we're not.

Don't believe that we're addicted to the making of lists, and less so to accomplishing them?

According to Harvard Business Review, the average professional has 150 tasks at any given time. Follow that up with a LinkedIn survey that found that only 11% of professionals actually complete their task lists.

We love to create lists! We rarely get them done.

Willpower is a Limited Resource

That's because the human brain cannot work on two things at once. We think we can, but our brain is actually switching between tasks. And the more tasks we work on, the more taxing it is on our brains. And our will power.

Science has found that willpower is a limited resource. When we exhibit willpower on a single task, we actually lose willpower to work on the next task. And so on down the line - until we don't have enough energy to complete the tasks on our list.

The same is true for goal setting. The more goals we make, the less likely they are to be achieved. In fact less than 8% of New Year's Resolutions are ever kept.

It's not because we don't have the skills and talent to complete anything we set our minds to. In fact, we should set those big goals. It's because we set too many of them.

You Need Insane Focus on a Single Goal

That's why experts agree you should have an insane focus on a single goal. Devote all your time and resources to accomplishing that one thing.

And with that insane focus, you'll find that you accomplish more in less time with greater predictability. That in turn will give you the confidence to set even bigger and better goals.

So today, ask yourself this: What one thing will change my life the most next year?

That's your single goal for 2017.

(Oh... and when you've achieved that, move on to the next thing that will change your life the most.)