A controller can regulate a system only if it commands at least as much variety as the disturbances it must absorb.
A thermostat handling one variable cannot regulate a system with three independent disturbances. It is the formal reason simplified management dashboards fail to control complex operations.
In practice
- A support desk with one script cannot handle callers with four kinds of problem, and the queue is the visible symptom.
- A performance review with three ratings cannot distinguish six meaningfully different kinds of contribution, so it stops carrying information.
- Subject
- Design & Systems
- Essay
- The limits every design runs into