Companies aren’t families. They’re battlefields in a civil war. Yet despite this capacity for internecine warfare, most companies roll along relatively peacefully, year after year, because they have routines—habits—that create truces that allow everyone to set aside their rivalries long enough to get a day’s work done.

Once you understand that habits can change, you have the freedom and the responsibility to remake them. Once you understand that habits can be rebuilt, the power of habit becomes easier to grasp and the only option left is to get to work.

Cravings are what drive habits. And figuring out how to spark a craving makes creating a new habit easier.

There's a natural instinct embedded in friendship, a sympathy that makes us willing to fight for someone we like when they are treated unjustly.

As people strengthened their willpower muscles in one part of their lives—in the gym, or a money management program—that strength spilled over into what they ate or how hard they worked. Once willpower became stronger, it touched everything.

A movement starts because of the social habits of friendship and the strong ties between close acquaintances. It grows because of the habits of a community, and the weak ties that hold neighborhoods and clans together. And it endures because a movement's leaders give participants new habits that create a fresh sense of identity and a feeling of ownership.

Shampoo doesn’t have to foam, but we add foaming chemicals because people expect it each time they wash their hair. Same thing with laundry detergent. And toothpaste—now every company adds sodium laureth sulfate to make toothpaste foam more. There’s no cleaning benefit, but people feel better when there’s a bunch of suds around their mouth. Once the customer starts expecting that foam, the habit starts growing.