Nobody owns the composite outcome

What it looks like. Several components or agents each do their part correctly and a bad outcome emerges from the combination. Each component's logs show a clean slice. Asking who is accountable produces a list, not a name.

Why it fails. Accountability was assigned per component, but the failure is a property of the composition — which no component was scoped to evaluate and no owner was assigned.

Instead. Make implicit shared-frame assumptions explicit cross-component contracts and verify them at runtime. Register a single accountable principal who attests to the joint property for any action requiring multi-actor coordination, and treat the absence of such a principal as a blocking defect.