Example of compensation not tied to a time spent: a company might pay someone to do nothing, so this someone doesn't do something for a competitor.

Value sharing is a basic framework for compensation negotiation. Employee wants to get all the value derived from own contribution. Employer wants to pay absolute minimum employee is willing to accept. Paying more than derived value doesn't make economic sense, so compromise will be somewhere within this range. If acceptable minimum is below the derived value, compromise is impossible. Time spent working is a free variable in all this.