Apply Theory of Constraints

Find the single resource that caps a system's throughput, subordinate everything else to it, then elevate it — instead of optimizing parts of the system that aren't the limiting factor.

Why This Is Best Practice

Adopted by: APICS/ASCM (constraint management is a core body-of-knowledge domain in CPIM certification), manufacturers worldwide via Drum-Buffer-Rope scheduling (Ford, Boeing suppliers, Amazon fulfillment network design documented case studies), the Theory of Constraints Institute's certified practitioner network, and widely taught in MBA operations curricula alongside Lean and Six Sigma. Impact: Goldratt Institute case-study compilations and independent TOC literature reviews (Mabin & Balderstone, 2003, "The performance of the theory of constraints methodology," meta-analysis of ~80 published TOC implementations) report median lead-time reductions of ~70%, inventory reductions of ~49%, and revenue/throughput increases of ~63% across manufacturing and project environments. Individual documented cases (e.g., GM's Powertrain Division, Boeing) report double-digit throughput gains within a single fiscal year of implementing the Five Focusing Steps. Why best: Most process-improvement effort defaults to optimizing whatever is easiest to see or measure — busy workers, idle machines, backlog size at any one step. TOC's core insight is that a chain's strength is set by its weakest link: improving any non-constraint resource does not increase system throughput and often just moves inventory or wait time to the real bottleneck. TOC forces improvement effort onto the one point that actually changes the system's output.

Sources: Goldratt & Cox, "The Goal" (1984); Goldratt, "It's Not Luck" (1994); Mabin & Balderstone (2003), International Journal of Operations & Production Management; APICS/ASCM CPIM Body of Knowledge

Steps

The Five Focusing Steps — run them in order, and treat step 5 as a loop back to step 1, not an end point.