Dear Kanwal, i appreciate ur ingenious nature in intricately studying the subject matter i posted and making an absolutely relevant question about an assertive statement i mentioned in the note. while i respect your intution in going for reprocessing if the revenue generation is higher irrespective of the costs of reprocessing, i would like to stand over my statement on the following lines. While i made a response without paying too much thinking on the subject, now i thank u for the opportunity to think on ur lines as well. anyways let my try this out this way. step1: 100 pieces are produced. 80 are conforming. 20 nonconforming. suppose Cost of 1 piece is Rs.1.00. Step 2: At Zero defect level Cost of production= Rs.100.00 with Unit cost=1.00 With 20 non conforming pieces, Cost of production = 1.25 per piece or Rs.125.00 per lot. Step3: Cost of poor Quality = (Rs.125.00 - Rs.100.00) +(Rs. 20.00) Rs.20.00 the cost of nonconformance which would have been realised had the conformance been 100%. here it is notable to understand that: nonconformance aggravated the cost of conforming product by 25% Non conformance itself resulted in a loss of Rs.20.00 Which is 20% hidden loss. here the actual cost of the item is Rs.1.45 already Step 4: The big question of Reprocessing Decision: At this stage it is very critical to see to that that the process capability is really 100%. ie. one should be sure that No more than Rs.1.00 is spent on rework. This means an 100% conformance at this stage, lest the cycle repeats infinitesimally in the reverse process as in the case of credit creation by banks using Cash reserve ratio. At this stage if process capability is 100% then the cost would be Rs.20 for 20 pieces.(here i assume the cost of production as Rs.1 for reprocessing also because am loosing time and labour and marketing edge and i assume that within the same time frame i think i could produce 20 new pieces). Assuming we have exhausted the material and manufactured 100 pieces by this stage 2 then the cost of 1 piece would be=Rs.1.65 or Rs. 165.00 per lot of Hundred pieces. That is we are already 65% over and above the actual costs. let us now consider that we find that at step 4 we have 4 non conforming items.(ie. 80% process capability). Then i would leave it for u to evaluate the further cost of poor quality and aggravation in cost of production along with the hidden losses. its a bit fussy as of now to calculate but not difficult. i can do that even for u if u want me to do this serriously. Coming to the decision criteria of how long to proceed with rework or when to scrap it, i think we need to do the following: we need to find an optimum balance between profits regeneration capability Vs cost of poor quality. ie. when the cost of poor quality exceed the profit regeneration capability we need to go for scrap lest we can continue with reworking. However except in case of precious metals like gold, platinum or such things, rework is usually not resorted. (my knowledge is limited as of now) But one question i have is how many ppl are making businesses with more 100% profit potential. ie. if the cost of production is Rs.1, they sell the product at Rs. 2. Secondly, How far can we allow ourselves to perform with an incapable process efficiency system spending time on rework. thirdly Cant we make money by selling scrap and obtain some profit over its true value. ie when we sell non conformance pieces as scrap in a form that obtains its true value with munimum modifications, then we would be actually making our production costs less than Rs.1.00 in some cases can u understand why reputed electronic companies replace items instead of rectifying problems. Similarly, mobile companies don't go suing every customer who has not paid the bills because the cost of suing a customer and recovering the money are too far higher than the cost of bearing up the bil by companies themselves. While in my post i mentioned before, i was discussing only the cost of poor quality vs cost of production, u added strength to this discussion by adding the revenue regeneration capability of the nonconfromance items. seems like am getting into learning the subject more thoroughly. i would be glad to receive more information and feedback on the subject from ur end. can u please send me ur email id or telephone number so that we can discuss subject more seriously. am really interested in these subjects though my knowledge is limited. With regards srinivas