The easiest way to simplify a system is to remove functionality. Today's DVD, for instance, has too many buttons if all you want to do is play a movie. A solution could be to remove the buttons for Rewind, Forward, Eject, and so forth until only one button remains: Play.
But what if you want to replay a favorite scene? Or pause the movie while you take that all-important bathroom break? The fundamental question is, where's the balance between simplicity and complexity?
How simple can you make it? VS How complex does it have to be?
On the one hand, you want a product or service to be easy to use; on the other hand you want it to do everything that a person might want it to do.
The process of reaching an ideal state of simplicity can be truly complex, so allow me to simplify it for you. The simplest way to achieve simplicity is through thoughtful reduction. When in doubt, just remove. But be careful of what you remove.