steelwind101 is correct with his comment...the results you see all depend on the current condition of your paint. What car/color/year are you working on? What is the paint condition?
You already washed and clayed the car. The washing and claying have removed the majority of paint contaminants...most of which are above surface bonded contaminants...those that sit on top of the paint and give it a rough feel.
The purpose of the paintwork cleanser is to prepare the paint for your Last Step Product. Paintwork cleanser is often used on cars that will not undergo a polishing step (e.g., the paint does not have imperfections) - the idea is to wash, clay, paint cleanser, wax/sealant. If your paint has imperfections (swirls, RIDS, bird etching, etc.) then you will insert a polishing step.
If you use a small foam applicator...like the round Meguiar's foam applicator (tan/yellow in color) then, depending on the condition of your paint, after completing a section, e.g., a hood, you should notice some residue (contaminants) on the pad...this is an indication that it is working - keep in mind that the paintwork cleanser is removing embedded contaminants - those that didn't come off with the wash or clay.