We do have visibility if an OS image build fails (due to an invalid container file), but we need to make this error clearer to the user (specifically in the case that they want to do an upgrade and have a failed os image build). Marking the MCP as degraded isn't a viable solution because it doesn't indicate the true error that the osimage build failed, but either we need to
1. stall an upgrade if an os image build fails 
2. have another status reporting mechanism to convey the osimage build failed (in relation to upgrades)

this story was inspired from the bug https://issues.redhat.com/browse/OCPBUGS-49666