Rules of Optimization:
Rule 1: Don't do it.
Rule 2 (for experts only): Don't do it yet.

-- M.A. Jackson

More computing sins are committed in the name of efficiency (without necessarily achieving it) than for any other single reason - including blind stupidity.

-- W.A. Wulf

We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil.

-- Donald Knuth

The best is the enemy of the good.

-- Voltaire