Average Outgoing Quality (AOQ): The expected average quality level of an outgoing product for a given value of incoming product quality.

AOQ plot represents the relationship between the quality of incoming and outgoing materials.

When incoming lots are very good, the outgoing quality will be good.
When incoming lot is very bad, then also the outgoing quality will be good because poor lots get reinspected and fixed.

See the graph showing the relationship between incoming quality and outgoing quality.

The above AOQ plot is made for the following inputs: