We use Scrum and we make software products for other companies (I guess it's called B2B).
So, first subquestion: Who should be satisfied by the Development Team: the Product Owner or the Stakeholders? I believe both. But I think, that the main goal of the Development Team is to make the Product Owner happy as the single entry point of requirements and the "aggregator" of all other Stakeholders.
And this is the root of my question: all thought of the Product Owner will be subjective. Different Product Owners means different psychotypes. One of them may be generous with praise and be glad for any positive changes in the product. Others may always be dissatisfied. And if the Development Team produces a great increment he will only be a little less dissatisfied, than usual.
As Scrum Master I want to assess the level of customer satisfaction after each increment and search for a way to increase it. But how can we make an objective assessment of customer satisfaction
So:
Is asking the Product Owner's opinion enough?
Or, maybe it's a good idea to suggest that the Product Owner get formal feedback (like surveys) from other stakeholders?
Or maybe there are more formal methods for measuring such an abstract entity as customer satisfaction?
Finally, maybe it's better to not use this subjective measurement at all?