'client-controlled' originates from the combination of 'client' and 'controlled', where 'client' refers to a person or organization using the services of a professional person or company, and 'controlled' means having power over something.

'client-controlled' evolved from the need to describe systems or processes where the client has significant influence or management power.

Initially, it meant 'controlled by a client', and this meaning has largely remained the same in modern usage.