Perfect is the enemy of good; don't let perfectionism prevent completion.
Voltaire's 1770 line, borrowed from an Italian proverb. Its operational form is that the marginal value of further refinement usually falls below the cost of delay long before anyone stops refining.
In practice
- A report circulated at four-fifths finished in March changes three decisions; the same report perfected and issued in September changes none.
- A kitchen refit is held up eleven weeks over a tile finish nobody has mentioned since.