Why is user-centred development critical to successful systems development projects?

User centered development/design is important as ultimately it is the user that will be using the product. If only a developer knows how to navigate and use a product, no matter how useful said product my be. If its hard to use the product do to poor development or design then that product is a failure. No one wants to use something that they have to work at to use, even if it is once they get around the poor functionality of the thing to its very useful core. And it goes without saying if the product is a failure then it is a loss for the company as a whole. All the time and effort that went into making a seemingly good product that falls short due to bad development costs the company money. Focusing on the user throughout the process of development, doing user testing, getting feed back, making mock ups, keeping the design fluid and slowly refining the product down to something that will match both the needs of the user, and the company. That is the very essence of good UCD / UX Design.