• A commitment is a rule you've added for yourself. "I must exercise five times per week." But if you break that commitment, it can result in a backsliding effect.
• A habit is that behavior that happens automatically from a triggering situation.

The habit-forming philosophy is that you should do things slowly and steadily. Slow and steady leads to a more sustainable strategy for the long-run. But in many areas, this strategy doesn't apply.

• In many difficult projects, such as starting a business or going back to school, it is necessary to put in a bigger effort at the start.
• When learning a language, slow and steady may be disastrous initially as it tends to push people to passive learning techniques that are ineffective.

The mistake here is assuming slow or fast always works best, without first checking if your specific strategy will be the best approach.

We cannot assume that we can change our behavior in any way we please, and with enough time, the new behavior will become a habit.

• Behavior may never become effortless.
• A habit that requires you to sleep only four hours will eventually make you exhausted.
• We have a deep need for autonomy, competence, and relatedness. A habit that brushes one of these needs aside won't last.

• Habits are useful when you focus on patiently persisting over a long period, rather than short bursts.
• The behavior you require can eventually run on autopilot while not requiring lots of deliberate effort.
• You're looking to make long-term changes to your routine or lifestyle rather than a temporary condition.