In the following excerpt from his new book, Think Again, Wharton management professor Adam Grant explains why success often comes from surrounding ourselves with “disagreeable” people — skeptics who can point out blind spots, question assumptions, and help us overcome our weaknesses.

In 2000 Pixar was on fire. Their teams had used computers to rethink animation in their first blockbuster, Toy Story, and they were fresh off of two more smash hits. Yet the company’s founders weren’t content to rest on their laurels. They recruited an outside director named Brad Bird to shake things up. Brad had just released his debut film, which was well-reviewed but flopped in the box office, so he was itching to do something big and bold. When he pitched his vision, the technical leadership at Pixar said it was impossible: They would need a decade and $500 million to make it.

Brad wasn’t ready to give up. He sought out the biggest misfits at Pixar for his project — people who were disagreeable, disgruntled, and dissatisfied. Some called them black sheep. Others called them pirates. When Brad rounded them up, he warned them that no one believed they could pull off the project. Just four years later, his team didn’t just succeed in releasing Pixar’s most complex film ever; they actually managed to lower the cost of production per minute. The Incredibles went on to gross upwards of $631 million worldwide and won the Oscar for best animated feature.

Notice what Brad didn’t do. He didn’t stock his team with agreeable people — who tend to be supportive and polite. Agreeable people make for a great support network: They’re excited to encourage us and cheerlead for us. Rethinking depends on a different kind of network: a challenge network, a group of people we trust to point out our blind spots and help us overcome our weaknesses. Their role is to push us to be humble about our expertise, doubt our knowledge, and be curious about what knowledge we don’t have.

The ideal members of a challenge network are disagreeable — critical and skeptical. They’re fearless about questioning the way things have always been done and holding us accountable for thinking again. There’s evidence that disagreeable people speak up more frequently — especially when leaders aren’t receptive — and foster more constructive conflict. They’re like the doctor in the show House, M.D. or the boss in the film The Devil Wears Prada. They give the critical feedback we might not want to hear, but need to hear.

“The ideal members of a challenge network are disagreeable — critical and skeptical.”

Before Brad Bird arrived, Pixar already had a track record of talented people pushing boundaries. But the studio’s previous films had starred toys, bugs, and monsters, which were relatively simple to animate. Since making a whole film with lifelike human superheroes was beyond the capabilities of computer animation at the time, the technical teams balked at Brad’s vision for The Incredibles. That’s when he created his challenge network. He enlisted his band of pirates to rethink the process.

Brad gathered the pirates in Pixar’s theater and told them that although a bunch of bean counters and corporate suits might not believe in them, he did. The pirates rose to the occasion, finding economical alternatives to expensive techniques and easy workarounds for hard problems. When it came time to animate the superhero family, they didn’t toil over the intricate contours of interlocking muscles. Instead they figured out that sliding simple oval shapes against one another could become the building blocks of complex muscles.

I’ve watched too many leaders shield themselves from dissent. As they gain power, they tune out boat-rockers and listen to bootlickers. They surround themselves with agreeable yes-men and become more susceptible to seduction by sycophants. Research reveals that when their firms perform poorly, CEOs who indulge in flattery and conformity become overconfident. They stick to their existing strategic plans instead of changing course — which sets them on a collision course with failure.

We learn more from people who challenge our thought process than those who affirm our conclusions. Strong leaders engage their critics and make themselves stronger. Weak leaders silence their critics and make themselves weaker. This reaction isn’t limited to people in power. Although we might be on board with the principle, in practice we often miss out on the value of a challenge network.

In one experiment, after people got feedback from a partner, if they were criticized rather than praised, they were over four times more likely to request a new partner. Across a range of workplaces, when employees received tough feedback from colleagues, their default response was to avoid those coworkers or drop them from their networks altogether — and their performance suffered over the following year.

Some organizations and occupations counter those tendencies by building challenge networks into their cultures. From time to time the Pentagon and the White House have used aptly named “murder boards,” enlisting tough-minded committees to shoot down plans and candidates. At X, Google’s “moonshot factory,” there’s a rapid evaluation team that’s charged with rethinking proposals: Members conduct independent assessments and only advance the ones that emerge as both audacious and achievable.

“We learn more from people who challenge our thought process than those who affirm our conclusions.”

Hashing out competing views has potential downsides — risks that need to be managed. On the Incredibles sequel, a rising star named Nicole Grindle came in to co-produce the sequel. One of her concerns was that the volume of the arguments between highly accomplished leaders might drown out the voices of people who were less comfortable speaking up: newcomers, introverts, women, and minorities. It’s common for people who lack power or status to suppress their dissenting views in favor of conforming to the HIPPO — the Highest Paid Person’s Opinion. Sometimes they have no other choice if they want to survive.

To make sure their desire for approval didn’t prevent them from introducing dissent, Nicole encouraged new people to bring their divergent ideas to the table. Some voiced them directly to the group; others went to her for feedback and support. Although Nicole wasn’t a pirate, as she found herself advocating for different perspectives, she became more comfortable challenging Brad on characters and dialogue. “Brad is still the ornery guy who first came to Pixar, so you have to be ready for a spirited debate when you put forward a contrary point of view.”

The notion of a spirited debate captures something important about how and why good fights happen. If you watch Brad argue with his colleagues — or the pirates fight with one another — you can quickly see that the tension is intellectual, not emotional. The tone is vigorous and feisty rather than combative or aggressive. They don’t disagree just for the sake of it; they disagree because they care. “Whether you disagree loudly, or quietly yet persistently put forward a different perspective,” Nicole explains, “we come together to support the common goal of excellence.”

From Think Again by Adam Grant, published by Viking, an imprint of Penguin Publishing Group, a division of Penguin Random House, LLC. Copyright (c) 2021 by Adam Grant.