Lean: is a management model focused on creating continuous flow to deliver maximum value to customers, using the minimum resources needed: ie lean. Creating flow focuses on the reduction of the eight types of “waste” manufactured goods: overproduction, timeout, transport, processed excess, inventory, movements, defects, underutilized human potential.
Six Sigma: is a process improvement methodology focused on reducing the variability of the processes, obtaining or eliminating defects or failures in the delivery of a product or service to the customer. 6 Sigma’s goal is to reach a maximum of 3.4 defects per million events or opportunities (DPMO), meaning any default event of a product or service fails to meet the requirements of the customer. 1 Six Sigma uses statistical tools for the characterization and study of processes, hence the name of the tool, since sigma is the standard deviation gives an idea of the variability in a process and the objective of the Six Sigma methodology is to reduce this process so that it always falls within the limits set by customer requirements.