An excerpt from Lean Out: A Professional Woman’s Guide to Finding Authentic Work-Life Balance.

In the third grade, my teacher identified me as a high achiever. Aside from recognition, he “rewarded” me with the opportunity to write an extra report on a topic of my choosing every month. Being young and not having many commitments on my time, I happily accepted the additional challenge and added work. This began the formation of some of my unwritten rules about what is required for success—and what is required for praise.

Achievements fulfill the higher need that many humans have for accomplishment. We want to meet challenges and make contributions. We want to belong in our cultures. Achievement, however, is a quest that’s never-ending. It can be addictive—even dangerous.

Hedonic adaptation is the concept where, despite the occurrence of significant positive or negative events, your set point for happiness tends to return to a baseline over time. Despite experiencing a joyful moment, such as a marriage, a job promotion, or even winning the lottery, our happiness levels eventually go back to where they were before the external input that incited the perceived change. The classic example of how this works is when you buy a new car. At first, you admire your car and notice its pristine beauty or increased performance over your old car with every drive. Over time, the shiny newness fades, and driving the car doesn’t give you that same novel joy that it once did. It’s just an OK car.

Then, you feel the longing to get another car. That’s where the treadmill part comes in. Our expectations rise to meet the new status quo, which prompts us to seek out more ways to increase our perceived level of happiness. So, how does this apply to achievement? You likely grew up being told you’re smart. You might have been particularly good at math or English or something else. Getting praise gave you a sense of happiness, acceptance, importance, and maybe even love.

You continue to do more of what you’re “good at.” As you mature, you choose to focus your efforts on areas of self-perceived strength. You keep achieving, so people praise you more … and they reward you with more responsibilities. Former lawyer turned writer and happiness expert Gretchen Rubin said, “Making partner at a law firm is like winning a pie-eating contest and being told that the prize is more pie.”

This pattern continues from your school days straight into your career. Achievement is met with more praise and an accompanying wider set of responsibilities, because you do such good work, you can handle it. Our self-worth also gets woven into the treads on the treadmill of achievement. We form more unwritten rules related to our performance:

“I cannot fail, or people won’t love me.”

“I should be grateful I was given this opportunity/job/spot in a class.”

“What I really want to do with my life isn’t possible because it’s not reimbursable/billable/valuable.”

Soon, our lives are filled with tasks, goals, and projects that, despite feeding our sense of self-worth, relevance, or importance, may or may not be related to what actually matters to us. Priorities and time spent begin to misalign. Values and actions diverge. Roles and interests become mismatched … all while we’re not really looking.

Dawn Baker is an anesthesiologist and author of Lean Out: A Professional Woman’s Guide to Finding Authentic Work-Life Balance.