The KISS principle

KISS - Keep It Simple Stupid is a design principle that I learned in my DBMS class. During ER modelling / DB design, we would need to have our design really simple and not complicate unnecessarily. Simplicity is a design principle that is getting repeated everywhere. Most of the Security design principles are based on Simplicity. Matt Bishop in his book "Computer Security - Art and Science" says "Simplicity makes design and mechanisms easy to understand. More importantly, less can go wrong with simple designs". Software Engineering also brings in the principle of Simplicity and highlights on the pros of having a simple design. An example of how simplicity could impact / have the winning edge can be clearly seen through the successful products of apple. I've read that Mac users love Mac coz itz lot more easier to get the mundane things done on a Mac than on a PC. iPod has a simple / easy to use interface and so does iPhone. That is the power of KISS.
Some quotes relating to Simplicity -
---- "Simplicity is the ultimate sophistication." — Leonardo da Vinci
---- "If you can't describe it simply, you can't use it simply." — Anon