Right there, says it in the book... image - Lucífer

"When you begin developing a mod you should start small. Don't plan to write a Total Conversion (TC) from the very start. If you set goals that are too hard to reach, you'll get frustrated in the process of working towards them; and you may never be able to bring the vision to life. Everyone has ideas. Everybody thinks they have a revolutionary new game concept that no one else has ever thought of. You have to be able to implement your ideas or provide some useful skill. If you become a skilled or notable mod author, you will find people propositioning you to implement their ideas. Never join a project whose idea man or leader has no obvious development skills. Never join a project that only has a web designer. You have your own ideas. Remember that developing a mod doesn't mean much if you never release it."