New Year’s resolutions flop for many reasons—both fear and ambition play roles in their self-destruction.

New Year’s resolutions come at weird time of the year: after Thanksgiving gorging, stressful holiday shopping, Christmas cookies, and New Year’s Eve drinking.

Expecting to then wake up on January 1 and become a whole “new you” doesn’t really make sense—but every year millions of Americans perform this mental and physical binge and purge.

“It’s notorious for failure, yet we keep doing it,” Dr. Greg Soltanoff told Healthline. “It’s also a way to okay our behavior during the holidays.”

There are a few simple reasons why nearly 90 percent of New Year’s resolutions fail. And knowing them may help yours succeed.

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Dr. Coral Arvon, director of behavioral health and wellness at Pritikin Longevity Center and Spa, said the biggest thing people need to understand when achieving resolutions is the difference between changing habits and making resolutions.

“Often times, our resolutions are too large—[or] we make too many—and therefore we set ourselves up for failure,” she said. “To successfully achieve these resolutions, understanding that small, short-term goals are the most effective and taking resolutions one step at a time is the best way to succeed.”

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Personal trainer Maria Brilaki, founder of Fitness Reloaded, and author of Surprisingly…Unstuck, said people often set their goals too high, and the totality of the situation can backfire because once the initial excitement is gone, fear takes over.

“And that’s exactly how we start sabotaging ourselves,” she said. “Before we know it, we’re back to square one. We’ve stopped going to the gym or keeping a budget.”

Counseling educator Diane Lange said fear is the major reason people give up on their New Year’s resolutions.

“Fear is such a powerful emotion it can override our priorities and goals we set for the New year,” she said. “We can have a fear of failure, success, or just fear of change—stepping outside our comfort zones—that stops my clients in their tracks before their resolution becomes a habit.”

Lange said facing fears is an important step to achieving goals.

“It will take you outside your comfort zone, which is scary, but look at the big picture and what the change will bring you at the end,” she said.

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Health experts agree that the abrupt changes may seem exciting at first, but when we have to change a good part of our daily routine to achieve our goals, we become too scared to continue and fall back into bad habits.

Arvon offered the following tips:

  • “Make resolutions tangible and achievable. For example, instead of stating you will ‘lose 20 pounds in 2014,’ say that you will ‘walk everyday for 2 weeks’ or ‘cut out chocolate, ice cream and soda for 2 weeks.’”
  • “Understand how you can best be successful.” (People treat resolutions, goals, and habits differently. For instance, some people may need to write down goals to keep track, while others need to talk out their habits and goals.)
  • “Get group support from others on achieving your resolutions.”
  • “Set short-term goals. At Pritikin, we state that it takes 17 to 21 days to form a habit; therefore, keeping a goal for those 21 days will bring success.”
  • “Use positive motivation and small rewards to keep you focused.”
  • “Set your smartphone calendar to give you positive messages or reminders about your goals a few times per day.”

Brilaki, however, argues not just for small changes, but for extremely small changes. For example, she suggests instead of aiming to workout three times a week, you start with two squats a day. The change is so small, you won’t stop with just two.

“And that’s exactly how these small habits grow from ridiculously small to big,” she said. “It’s hard to resist not doing more, because it’s just so easy.”

Soltanoff, president and co-founder of the workplace wellness program Voom, said the bit-by-bit approach creates the lasting changes people want to see in their lives.

“The definition of success is doing the right things long enough consistently,” he said.

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Soltanoff stresses the “10 percent rule”: change 10 percent of habits each month. For people looking to improve their health, it could be adding a five minutes of stretching one month and replacing a morning pastry with a piece of fruit the next.

“We see once there’s a large disruption in your daily schedule—such as going to the gym for an hour—it ultimately fails because it’s too big of an interruption,” Soltanoff said. “If everyone had that process, those little changes, on Jan. 2 if they try to replace one meal a day with something a little healthier, that’s going to be more successful.”

Soltanoff said his New Year’s resolution is to “not make any more resolutions.”