There are benefits to keeping things simple: it creates clarity, reduces complexity, and can increase productivity. Simple does not mean boring or uninteresting.
Achieving simplicity in design is a matter of having a clear understanding of the problem that you are solving and continually working to reduce a prospective solution to it's essence. Any more or any less and you will have missed the mark. Pushing a design to the brink of failure requires discipline, rigor, and a willingness to let go of ideas.
And knowing when to stop.