Definitions: (1) directly producing the desired result with a minimum of effort, expense, or waste; (2) working at optimum proficiency; (3) wise progress; competent; capable
See also: Effective

Synonyms: able, causative

Quote: People, like everything else, work better in parallel than they do in series. . . . When things are organized socialistically in a bureaucratic series, any increase in complexity increases the probability of failure. But when they’re organized in a free-enterprise parallel, an increase in complexity becomes an increase in diversity more capable of responding to Dynamic Quality, and thus an increase of the probability of success. — Robert M. Pirsig (1928 – ) Lila