What do you need to be a great engineer?

If you haven't read Founders at Work, you definitely should. Reading this I've enjoyed every page. Probably this book is more about "experience sharing" than any other book. This book has 33 co-authors each sharing his insight into key components of success. I just could not resist posting these words of wisdom of Steve Wozniak:

Livingston: What is the key to excellence for an engineer?

Wozniak: You have to be very diligent. You have to check every little detail. You have to be so careful that you haven't left something out. You have to think harder and deeper than you normally would. It's hard with today's large, huge programs

By the way the whole interview with Steve is publicly available. Take your time reading it.