Optimization: Your worst enemy

Optimization is what you do when the performance is insufficient. Sometimes the optimizations are easy, sometimes they are hard. Sometimes they fly in the face of your original design, and sometimes they require that you grossly violate your beautiful abstractions in your class system. But always, and I repeat, always, my experience has been that no programmer has ever been able to predict or analyze where performance bottlenecks are without data. No matter where you think the time is going, you will be surprised to discover that it is going somewhere else.