Entities should not be multiplied beyond necessityThe corresponding idea of being "customer focused" or "customer driven" is certainly nothing new, but it too needs to extend throughout the entire organization.
Too often, software companies become development-focused and try to create the mother-of-all-applications. Simple ideas are vastly over-architected, and the methods required to implement them become foreign to those who would use it.
Never loose sight of the target market. Make things functional but simple (versus simplistic). It can be done.