The bottleneck
Why everyone is busy and work still waits.
The short film
A process can only finish work as fast as its slowest step.
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Complete video transcript
Picture a shop where everyone's busy. Phones get answered, quotes get written, and customers still wait. Work moves through steps, and every step can only handle so much in a day.
Here, Review handles the least. One person signs off on every quote. So finished quotes pile up in front of Review, while Schedule, the step after it, sits half empty.
The instinct is to speed up the steps you can see. Add someone at Intake. Write quotes faster. But no more jobs get booked. The pile just grows.
A process can only finish work as fast as its slowest step.
So start there. Pull one waiting quote. Was it really ready, or was a price missing? A pile shows you where, not why.
Then protect that step. Send it only work that's ready. Pace everything else to it. And add capacity last. And when it starts to move, the constraint moves too. Find the next one.
Four steps. One sets the pace.
Work piles up in front of the slowest step. Speeding up Intake or Quote only makes that pile bigger.
In one sentence
A process can only finish work as fast as its slowest step. Improve anything else and you mostly grow the pile.
Use it when
- Everyone is busy, but customers still wait.
- You added people or hours, and things didn't move faster.
- Work keeps stacking up in the same place.
In a service business
More prep won't fix a full oven.
A pizza shop can add a second person making dough. If the oven is already full, the extra pizzas just wait on the counter.
The same thing happens with quotes. If finished quotes wait for the one person who can approve them, drafting more quotes only makes a bigger pile. Before you hire another reviewer, check one waiting quote: was it actually ready, or was a price missing?
The five focusing steps
- IdentifyFind the step where work waits.
- ExploitMake sure that step never sits idle or does avoidable work.
- SubordinatePace the other steps to it, not to their own speed.
- ElevateAdd capacity only after the first three.
- RepeatOnce it moves, a new constraint appears. Start again.
Where it stops being useful
Where it comes from
Eliyahu M. Goldratt introduced the Theory of Constraints in his 1984 business novel The Goal, written with Jeff Cox. This explainer is our own summary.