Betsy Schow didn’t want to be a contender: She wanted to be the best.

Instead, she ended up being bogged down by increasing weight gain, plummeting self-esteem and a paralyzing perfectionism that kept her from finishing anything.

After she lost 75 pounds and ran a marathon (which she chronicled in her book, “Finished Being Fat”), Schow realized that her perseverance helped her as much as diet and exercise.

In her new book, “The Quitter’s Guide to Finishing,” Schow gently instructs the quitter in all of us to set personal goals and power through to the finish line.

Q: Is quitting really that big of a problem?

A: Everyone has been a quitter at one time or another, on one project or another. And that’s OK. But when you quit a lot, it starts to mangle your self-worth. That’s when it becomes a problem. Quitting builds a wall of failures and it can be tough to get over that wall. 

Q: What’s your definition of a quitter?

A: A quitter is someone who gets all excited about starting a project — any project — but never finishes it. Instead, they move on to the next and the next.

A quitter is someone who intends well — they’re not lazy or stupid — but they have this negative inner voice in their head that keeps them from getting through the hard work to finishing. 

Q: What does that inner voice say?

A: “You can’t do this.” “You’ll never finish.” Stuff like that. It eats away at your self-worth. And then you start to think you’re not good enough, that you don’t deserve whatever it is you’d get by sticking with it — losing weight, getting a better job. 

Q: It sounds like a downward spiral.

A: Yes, but the good news is finishing works the same way. Once you finish one project, you realize that you can finish other things. You find that, yes, you can do it. And that can change the direction of your life. 

Q: You make it sound easy.

A: No. It’s hard work. It sucks, because you have to change your perception and let go of perfection. I say: Not everyone can win the race, but everyone can finish. And I’ve learned to redefine failure. It isn’t a failure if you can’t do something perfectly — failure is not finishing. 

Q: What are the biggest challenges for quitters?

A: Beginnings aren’t a problem. Quitters tend to get really excited about starting something. The key is to use that kickoff energy to get through the mushy middle, when things get hard or boring. 

Q: What’s the best way to push through that mushy middle?

A: Slice the work into small pieces. If you’re halfway through a marathon, don’t say “I’ve got 13 miles to go. I can’t make it.” Say, “I can make it one more mile.” You’ll probably find you can make it that mile, and the next one and the next one.

Set honest goals and deliver on your promise — to yourself — to meet those goals. You may not be able to lose 20 pounds. But if you set a goal of going to the gym three times a week and you do that, then you’ve been successful. 

Q: Are you still a quitter?

A: I was a quitter, now I’m a reformed quitter. I still have that perfectionist in me that wants to be the best, but I’ve learned to pace myself, set priorities and figure out what’s really important to me.