You can learn more from failure than success. In failure you're forced to find out what part did not work. But in success you can believe everything you did was great, when in fact some parts may not have worked at all. Failure forces you to face reality.
Fred BrooksThe management question, therefore, is not whether to build a pilot system and throw it away. You will do that. Hence plan to throw one away; you will, anyhow.
Fred Brooks