The Traditional Yield is taken at the final step of a process to measure the effectiveness of the overall process. This type of measurement does not take into account scrap, rework or any other inefficiencies in a process it only looks at what goes in and what comes out.
John is machining 5 parts today. During the machining phase 2 parts are oversized. John goes back and machines the parts down to size and they pass inspection giving him 5 good parts. His yield on the 5 piece run was 100%.