A decentralized contract consensus is not a center deciding for everyone. Its value is that each party states the terms first and still honors them later.
When no center can decide at any moment, terms written in advance tell the customer, the engineers, and the plant what happens next. That expectation is why the work can continue.
The person who brings the need, the people who make the tool, and the floor that uses it each keep their own part. A promise left with an unseen head office has no weight.
The same agreement can travel to a similar plant. The next party joins on terms already stated, without bargaining again over who decides.