Why “Six”?? Achievement 99% Enough?

Our Next question is Why use Six as the target of Six Sigma Activities? As the main goal of Six Sigma are creating errors or defects 3.4 per millions. This number compared by its success (999,996.6 devices) is too small or near to Zero or perfect condition. That’s why this condition wants to be achieved and implemented in our organization process.

For more objectives, in the Six Sigma activities we use σ (Sigma)-level to reflect our process capability. Based on the statistical research shown that 3.4 defects/error per million equal if our process capacity reach 6 Sigma Level. Detail defect compared with its Sigma Level will shown table bellow.

Picture IN.5 Sigma Level Impact

Refer to illustration above, indicated that 99% accurate in process is not enough to become world class organization. If our process capability has got 99% (refer to 3σ) we still have a big number of errors / failures / defects. Only if we reach Six “σ” we can reduce the process in small error.