Bottle Neck

Peanut butter and pickles come in jars; their contents can (in principle, at least) get out at 32'/sec^2. Soda and wine come in bottles whose necks slow their contents' flow.

EliyahuGoldratt argues (persuasively, I think) that every process is constrained by a (single!) bottleneck at a particular time. The one stage in the process that has less capacity than any other is its bottleneck. "Bottleneck" and "constraint" are synonyms in his TheoryOfConstraints.

Manufacturing, project, and other managers can avoid spreading themselves too thin (peanut butter again!) by focusing on the bottleneck in each of their processes.

Goldratt's business novels are readable if not literary. TheGoal has the basics with a generic manufacturing example, ItsNotLuck looks at marketing (cosmetics, printing, and backup generators), CriticalChain does ProjectManagement, and NecessaryButNotSufficient? considers broader business issues. His technical books are difficult, though.

H. William Dettmer's analytic books are well done. Breaking the Constraints to World-Class Performance is a textbook (user's guide) and Goldratt's Theory of Constraints: A Systems Approach to Continuous Improvement is an encyclopedia (reference manual). Both are from ASQ's Quality Press (qualitypress.asq.org).

-- GeorgeBrower

Some sources criticise Goldratt for being excessively simplistic. See TheGoal

No doubt. Any first shot at explaining something is likely to suffer from excessive simplicity. Imagine how hard it must be for a physicist to explain himself in a novel! His nonfiction goes way the other way -- it's just plain dense! The Goal is a good introduction for people with manufacturing backgrounds, but after that there's better stuff. His other novels are good if you want a quick view but Dettmer's books, especially Breaking the Constraints, are both thorough and at least as clear as any other User's Guide -- Reference Manual pair. I just hope people don't blow off his ideas because he's not an artistic novelist. --GeorgeBrower

This seems like one of those "obvious in hindsight" things that may have been obvious all along. Of course a process is limited by its earliest slowest step. It always will be. There is only a problem when that speed is below the desired speed.

CategoryManufacturing