Prominent computer scientist and mathematician Donald Knuth famously stated:
Premature optimization is the root of all evil.
I, personally, hold that money is the root of all evil, but premature optimization is definitely up there!
Why is premature optimization so evil? Well, there are a few reasons. First, programmers can sometimes be pretty bad at identifying what the bottleneck of a program - the routine or routines that have the slowest throughput - is, and optimize the wrong parts of a program. Identification of bottlenecks can most accurately be performed by profiling your code after it's been completed in an un-optimized form.
Secondly, clever tricks and shortcuts for speeding up code often...
