Questions for all:

A ways back, I read an on-line article that explained that the real obstacle in performing process analysis for lean six sigma projects was identifying process inputs.  The article stated that, typically, identification of process outputs was realatively strainght forward, but that, even the experts on a process had difficulty identifying the inputs.

Unfortunately, I can not re- locate that article.   Can anyone direct me to other written discussions of such?  Or does anyone have any experiences that would confirm or refute such?

Thanks,

Tony Markos