what is meaning of six sigma? in total quality management ? and why they name it?

Question

total quality management

Answer 1

Six-sigma (1)is a process (define, measure, analyze, improve, control) to improve existing processes falling below specification by looking for incremental improvement through elimination of process variables that cause defects. (defined as unacceptable deviation from the mean or target.)

Developed by Motorola (2)(3) thereof, the emphasis is placed on data collection, and analyzing results to reduce defects in products and services.

Six sigma is mostly applied with high technological industries, such as Seagate.

The measure of negative deviation used six standard deviations. It has since gone beyond “error reduction/correction” or defect control.

Answer 2

No, they want results to all be WITHIN six sigma of the mean. That means producing the right results 99.73% of the time, making sure there are no defects in the process.

Many companies have benefitted greatly from analyzing their processes to find out what exactly is causing defects.

Just look up "Total Quality Management"; you'll find a ton of material. The US Government is excited about it, too.

Answer 3

They want to convince people they are six standard deviations (the symbol for which in statistics is a greek lower case sigma) from the mean in their quality.

My opinion, having read some of their writing, is that it's simply propaganda for the rubes, hoping to get someone gullible enough to pay them. I see many better writers with more concrete suggestions out there.