Theory of constraints (TOC) is an idea that every system has at least one constraint. With theory of constraints you identified constraints and then try to focus the process and value flow around it. TOC is adopts the idea that “a chain is no stronger than its weakest link”.
And only when you increase the flow through the constraints the overall throughput will rise. Constraints can be internal and external. An internal is usually when the market demands is higher than the throughput of the system. And external can be the opposite, when the system produce more than the market demands.
When you get rid of a constraints it appears somewhere else in the system. It’s impossible to get rid of them all and that’s when “buffers” comes in handy. Buffers is placed before an constraint to make sure it never starves and behind to make sure it doesn’t blocks other constraints.
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