What is the Key Indicators for the success of business operation particularly in manufacturing environment?

It depends on the strategic goals of your Company.  There is a write up about28 manufacturing metrics that you may find interesting: http://blog.lnsresearch.com/blog/bid/188295/28-Manufacturing-Metrics-that-Actually-Matter-The-Ones-We-Rely-On

People in different positions may have difrerent weightage on the KPIs, e.g. Production engineer would think that Cycle time is important.  QA would go for yield/% non-conformance.  HSE people on number of incidents.  The boss may just want to see the bottom line... :-)

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