Relying on Habits

"There is a theory of human behavior that says people subconsciously retard their own intellectual growth. They come to rely on clichés and habits. Once they reach the age of their own personal comfort with the world, they stop learning and their mind runs on idle for the rest of their days. They may progress organizationally, they may be ambitious and eager, and they may even work night and day. But they learn no more. The bigoted, the narrow-minded, the stubborn, and the perpetually optimistic, have all stopped learning." -Philip Crosby

A habit requires less energy from the body than learning something new - which is why we have so many of them. We should still be actively learning new things rather than relying on the things we've grown accustomed to.