Wirth's law is Niklaus Wirth's variant of the Jevons paradox: Software is getting slower more rapidly than hardware is getting faster.

Wirth presented this idea in 1995 in an article as a means to justify the need for "lean software", something like Wirth's own ?Oberon system.

For future scenarios where hardware stops getting faster and may actually start getting smaller and simpler, we may envision an inversion of Wirth's law: software will be getting better more rapidly than hardware will be getting smaller.