My thoughts on the data vending machine protocol
Read the protocol. Looks not great incentive wise/business best practices wise.
The user tips after the work is done, but why not take the work and not bother with the tip?
On the other hand, if it wasn't like this, what could users do about scammers taking the money with terrible output.
In business, the norm is to find businesses with a reputation, and pay them whether they do a good job or not. If the business does a bad job, that affects their reputation, and they then have a harder time getting business.
This protocol suggests to reverse the roles. That providers should only take jobs from customers with a good reputation. However, there are significantly more customers than providers and it is much more difficult to scale this reputation system as a result.
(Its also important to note that I derived what I expect to happen in this protocol and not merely what the protocol explicitly states)