But there are two main types of motivation, and the type of motivation that drives us along actually has an impact on how well we do our job.
External motivation is motivation that comes from outside of our own brain. When you want to do a job because it will impress someone, or because you'll receive a prize for it, or because you'll be punished if you don't--that's motivation that comes from outside your internal value system.
Internal motivation is the driving force that comes from inside us, and causes us to do a good job because we feel good about ourselves when we accomplish something. When we are internally motivated, we operate according to our own values.
It's important to recognize what's driving you along, and to build a sense of pride in your work. It's OK to make other people proud of you--but it's also important that you impress yourself from time to time.