When you are setting a goal, by all means engage in lots of positive thinking about how likely you are to achieve it. Believing in your ability to succeed is enormously helpful for creating and sustaining your motivation. But whatever you do, don’t underestimate how difficult it will be to reach your goal. Most goals worth achieving require time, planning, effort, and persistence. Studies show that thinking things will come to you easily and effortlessly leaves you ill prepared for the journey ahead and significantly increases the odds of failure.

There are quite a number of motivational speakers and self-improvement books with a surprisingly simple message: believe that success will come easily to you, and it will. There is one small problem in this argument, however, which unfortunately doesn’t seem to stop anyone from making it: it is utterly false.

In fact, not only is visualizing “effortless success” unhelpful, it is disastrous. This is good advice to give only if you are trying to sabotage the recipient. It is a recipe for failure. And no, I’m not overstating it.

But how can this be? Isn’t optimism a good thing? Yes, optimism and the confidence it generates are essential for creating and sustaining the motivation you need to reach your goals. Optimists are also physically healthier, recover more quickly from illnesses, suffer less frequently from depression, are better at prioritizing and multitasking, and more easily adapt to adversity and challenges.

When you think about it, this is hardly surprising. Albert Bandura, one of the founding fathers of scientific psychology, discovered decades ago that perhaps the best predictor of individuals’ success is whether or not they believe they will succeed—something optimists do naturally. Thousands and thousands of experiments later, he has yet to be proven wrong.

But there is an important and often overlooked caveat: to be successful, you need to understand the very vital difference between believing you will succeed, and believing you will succeed easily. Put another way, it’s the difference between being a realistic optimist, and an unrealistic optimist.

Realistic optimists (the kind Bandura was talking about) believe they will succeed, but also believe they have to make success happen—through things like effort, careful planning, persistence, and choosing the right strategies. They recognize the need for giving serious thought to how they will deal with obstacles. This preparation only increases their confidence in their own ability to get things done.

Unrealistic optimists, on the other hand, believe that success will happen to them—that the universe will reward them for all their positive thinking, or that somehow they will be transformed overnight into the kind of person for whom obstacles cease to exist. (Forgetting that even Superman had Kryptonite. And a secret identity that took a lot of trouble to maintain. And also relationship issues.)

One of the clearest illustrations of the dangers of unrealistic optimism comes from a study of weight loss. Psychologist Gabriele Oettingen asked a group of obese women who had enrolled in a weight-loss program how likely they felt they were to reach their goals. She found that those women who were confident that they would succeed lost twenty-six pounds more than self-doubters, as expected.

But Oettingen also asked the women to tell her what they imagined their road to success would be like—if they thought they would have a hard time resisting temptation, or if they’d have no problem turning down free doughnuts in the conference room and a second trip to the all-you-can-eat buffet. The results were astounding: women who believed they would succeed easily lost twenty-four pounds less than those who thought their weight-loss journey would be no walk in the park.

She has found the same pattern of results in studies of students looking for high-paying jobs after college, singles looking to find lasting love, and seniors recovering from hip replacement surgery. Realistic optimists send out more job applications, find the courage to approach potential romantic partners, and work harder on their rehabilitation exercises—in each case, leading to much higher success rates.

Believing that the road to success will be rocky leads to greater success, because it forces you to take action. People who are confident that they will succeed and equally confident that success won’t come easily, put in more effort, plan how to deal with problems before they arise, and persist longer in the face of difficulty.

Unrealistic optimists are less likely to consider all the possible turns the path to their goal might take. They are more likely to take risks without thinking things through. And they are only too happy to tell you that you are “being negative” when you dare to express concerns, harbor reservations, or dwell too long on obstacles that stand in the way of your goal. In truth, this kind of thinking is a necessary step in any successful endeavor, and it is not at all antithetical to confident optimism. Focusing only on what we want, to the exclusion of everything else, is just the kind of naive and reckless thinking that has landed industry leaders (and at times entire industries) in hot water.

Cultivate your realistic optimism by combining a positive attitude with an honest assessment of the challenges that await you. Don’t visualize success; visualize the steps you will take in order to make success happen.

Putting It into Practice: Be a Realistic Optimist

1. Perhaps the single most effective way to increase your confidence is to reflect on past successes. When you find yourself full of self-doubt, take a moment to recall (as vividly as possible) some of the goals you have achieved, and the obstacles you overcame to do it. You can even make this an if-then plan: If I am doubting myself, then I will remember the time that I _______________. Studies have shown this to be an effective strategy for increasing confidence with both anxious test takers and jittery pregame athletes.
2. To keep your optimism realistic, think carefully about the obstacles, difficulties, and setbacks you are likely to encounter as you pursue your goal. Just as important, visualize how you will deal with each challenge. If your first strategy doesn’t work, what’s plan B? (This is another great time to use your if-then plans.) Remember, it’s not “negative” to think about the problems you are likely to face, but it is foolish not to.