We all use imperfect software every day; little frustrations mentally accumulate in a way that little victories do not.

Eric Lippert

One key to effective programming is learning to make mistakes quickly, learning from them each time. Making a mistake is no sin. Failing to learn from a mistake is.

Steve McConnell, Code Complete, Second Edition

The bottom line on experience is this: if you work for 10 years, do you get 10 years of experience or do you get 1 year of experience 10 times?

Steve McConnell, Code Complete, Second Edition