Rob Pike on simplicity in the context of engineering at Google circa 2009:

Simpler things are easier to understand, easier to build, easier to debug, and easier to maintain.

Complexity just happens and its costs are literally exponential.

On the other hand, simplicity takes work—but it's all up front. Simplicity is very hard to design, but it's easier to build and much easier to maintain. By avoiding complexity, simplicity's benefits are exponential.

The same principles hold equally true in the design of mechanical timepieces.