Outcome pricing is a piece rate
Metronome's pricing levers page sets out the choices a software company makes when it prices a product. There are five levers: the metric it charges for, the structure of its tiers, the commercial model, the incentives, and how it charges for support. Most of the argument about AI pricing is about the first lever, and its options sound new: per seat, per token, per outcome. They are three old ways of paying for work. A seat is a salary, a token is an hourly wage, and an outcome is a piece rate.

The bottom rows of the figure show what each form does with risk. A salary and a piece rate both leave the seller to absorb a job that runs long, but only a piece rate also leaves the seller to absorb a job that fails. Labour economics has studied all three forms for decades, and it knows when piece rates work: when the job can be counted, when bad work can be seen, and when the worker has a floor under the slow weeks. Those conditions will decide where outcome pricing holds. One more lever, the commercial model, comes back at the end, where it turns out to manage the risk the metric creates; tiers, incentives and support pricing stay out of this post.
Left: the Machine Ledger, what the harness produces. Right: the Human Ledger, what producing it does to the person.