Measure twice, cut once...

I will never be able to stress the importance of test and evaluation. Over the last year I have been challenged with projects that have not been adequately tested, resulting in changes to the basics of a project that derail the ability for immediate success of a product. Oversight is common, however, blatant disregard for proper consideration of function and form in a new product is often suicidal for a product launch. More often than not a new project is rushed to market well before it is ready, resulting in costs, both financial and opportunity, that cannot be accounted for and an eventual loss beyond whatever could normally be expected.

So the moral to my story is - Test your great idea thoroughly before you think you should be making money from it, then test it again to make sure.