When someone tries to submit the module build and some components are submitted for a build and the module build fails but the submitted components are not removed from the Koji, there can be a situation where the same module and component is submitted for a build for second time, but the first Koji build of this component finishes before the second one.

The first component build is then ignored, because its task_id is not the one expected by Orchestrator (it expects the second build task_id).

The second build later fails, because there is NVR collision with the first (ignored) build.

Example of such builds: http://koji.stg.fedoraproject.org/koji/taskinfo?taskID=90017310 and http://koji.stg.fedoraproject.org/koji/taskinfo?taskID=90023728