Where Six Sigma can take business ?
Six Sigma Addresses reducing variation in product or service to satisfy customer requirements which are more specific and measurable.
Any thing that does not meet customer requirements can be called as defect. There is always some uncertainty about customers requirements and standardization of improvement aimed at it.
According to Kano Model , the customer requirements are dynamic.
Hence Six Sigma can take a company up to the level of only customer satisfaction and not much to the delight state
Six Sigma mainly helps to repair and not replace ( Though some portion in addressed at DFSS when no significant result from incremental improvements by DMAIC)
Hence Six Sigma cannot address issue as a whole system including the less tangible ones . Hence there is a need for PDSA and SOPK for continuous improvement