🐢 You are reading The Long Start — Module 5 of 10

This is the nerdy math module. Don't worry — we use very small words. Missed Module 4?

The Single Most Expensive Question in Manufacturing

"Where should I put my people?"

Every shift, every day, every supervisor answers this question. And most of them answer it the same way: "Put people where I put them yesterday." Or: "Put 3 on receiving, 5 on assembly, 2 on shipping — that's what we always do."

The problem? "What we always do" was probably a guess the first time. And that guess gets copied forever. Meanwhile, cycle times change, demand changes, headcount changes, and nobody recalculates.

The Cost of Guessing

Research shows that unbalanced staffing wastes 15-30% of labor capacity. Let's do the math on that. Say you have 50 people at $20/hour, working 2,000 hours/year. That's $2,000,000 in labor costs. 15-30% waste = $300,000-$600,000/year lost because people are standing in the wrong spots. This module explains how to stop that.

Theory of Constraints (TOC) — The Big Idea

Where to learn more: Full Theory of Constraints Guide

The ELI5 Version

Imagine a highway with 3 lanes that merges into 1 lane. No matter how fast cars go in the 3-lane section, everyone slows down at the merge point. That merge point is the bottleneck. It controls the speed of the entire highway.

Your factory works the same way. You might have 10 process steps, but ONE of them is slower than the rest. That one step limits your entire output. It doesn't matter if every other step is blazing fast — you can only produce as fast as your slowest step.

Theory of Constraints says: find the bottleneck, and focus all your effort there. Put more people on it. Speed it up. Remove obstacles from it. Because every minute you save at the bottleneck is a minute saved for your entire operation. Every minute you save at a non-bottleneck... is worthless. The other steps are already fast enough.

The Lemonade Stand Analogy

You run a lemonade stand with 3 steps:

  • Step 1: Squeeze lemons — you can do 60 cups/hour
  • Step 2: Mix sugar and water — you can do 100 cups/hour
  • Step 3: Pour into cups — you can do 80 cups/hour

How many cups of lemonade can you sell per hour? 60. Not 100. Not 80. Sixty. Because Step 1 (squeezing lemons) is the bottleneck. It doesn't matter that Step 2 can do 100/hour — it's sitting idle 40% of the time waiting for Step 1.

If you get a second lemon squeezer, Step 1 can now do 120/hour. Your new bottleneck becomes Step 3 at 80/hour. Output jumps from 60 to 80 — a 33% increase — by focusing on one step.

Auto-Assign Staff — One Button, Big Impact

Where to find it: The "Auto-Assign Staff" button in My Day or the Process Planner

What It Does (Step by Step)

When you tap "Auto-Assign Staff," here's what happens behind the scenes in about 2 seconds:

Reads your process modelThe algorithm looks at every stream, every step, every cycle time, and every dependency you've set up.
Finds your bottleneckIt calculates which step is limiting your total throughput right now, given current staffing. This is the constraint.
Allocates people to the bottleneck firstThe bottleneck gets priority. If adding one person to the bottleneck increases throughput more than adding one person anywhere else, the bottleneck gets the person.
Fills remaining stepsAfter the bottleneck is staffed, the algorithm distributes remaining people to other steps, ensuring none of them become the new bottleneck.
Shows you the resultEvery step displays its assigned headcount. Bottlenecks are flagged in red. On-track areas are green. Overstaffed areas are blue.

What You Can Do After Auto-Assign

ActionWhat Happens
Accept the recommendationUse the suggested staffing. Print it or display it for your team.
Override manuallyMove people around yourself. The system recalculates throughput in real time as you adjust.
Change headcount3 people called out? Adjust the number. Tap auto-assign again. New plan in 2 seconds.
Switch shiftsDifferent shifts have different step activations. Switch to see the optimal plan for each shift.
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Why this beats a spreadsheet: A spreadsheet can hold a staffing plan, but it can't recalculate in 2 seconds when 3 people call out sick. Auto-Assign does. Every time headcount changes, you get a new optimal plan instantly.

Manpower Analysis — "What If?" for Staffing

Where to find it: Manpower Analysis

What it is: A sandbox where you can test different staffing scenarios without actually changing anything. "What if we had 25 people instead of 20? What if we added 3 people to Assembly? What if we removed 2 from Shipping?"

Why This Matters

Before you ask your boss for more headcount, you need to prove the ROI. "I need 3 more people" is a request. "Adding 3 people to Assembly increases throughput by 18%, which translates to $450K in additional output per year at a cost of $150K in labor" is a business case. Manpower Analysis gives you the data for that business case.

What You Can Do

Capacity Planning — How Much Can We Actually Do?

Where to find it: Capacity Planning

What it is: A tool that answers: "Given our current equipment, people, and process, what's the maximum we can produce? And when will we hit that limit?"

Why This Matters

If your capacity is 1,000 units/day and demand is 800 units/day, you're fine. But demand is 950? You're one bad day away from missing targets. Demand is 1,100? You need more capacity — which means more people, more shifts, or more equipment. Capacity Planning tells you when that cliff is coming so you can prepare instead of panic.

What You See

Push vs Pull Simulator

Where to find it: Push vs Pull

What it is: An interactive demo that shows the difference between push and pull production systems.

Push vs Pull in ELI5 Terms

Push: You make stuff and push it forward whether the next step is ready or not. Like cooking a huge batch of food before anyone shows up. Result: stuff piles up between steps (WIP), lead times balloon, and if demand changes, you're stuck with extra inventory.

Pull: You only make stuff when the next step (or the customer) asks for it. Like cooking food to order at a restaurant. Result: less WIP, shorter lead times, less waste from overproduction.

The simulator lets you see both systems side by side and watch how WIP, lead time, and throughput differ. It's one of those things that's easier to understand when you watch it happen than when someone explains it with words. (We know. We just used a lot of words.)

Theory of Constraints Tool

Where to find it: Theory of Constraints

What it is: A dedicated learning and calculation tool for TOC. It walks you through the Five Focusing Steps of TOC with your actual data:

1. Identify the constraintFind the bottleneck — the step limiting your system's output.
2. Exploit the constraintGet the most out of the bottleneck without spending money. Remove breaks, reduce changeover time, eliminate quality issues at that step.
3. Subordinate everything elseMake every other step serve the bottleneck. Don't overproduce at non-bottleneck steps — it just creates WIP.
4. Elevate the constraintIf you've squeezed everything out of the bottleneck and it's still the constraint, invest: add people, buy equipment, redesign the process.
5. RepeatThe old bottleneck might not be the bottleneck anymore. Go back to step 1 and find the new one.

Summary: The Staffing Tools

ToolWhat It DoesWhen to Use It
Auto-Assign StaffDistributes headcount optimally using TOC mathEvery shift — after entering today's headcount
Manpower AnalysisWhat-if scenarios for staffing changesWhen building a case for more (or fewer) people
Capacity PlanningMaximum output analysis and projectionsPlanning for demand growth or new products
Push vs PullInteractive demo of production system typesLearning and training
Theory of ConstraintsGuided TOC analysis with your dataDeep-dive improvement projects focused on the constraint

What's Next?

The math is done. Your brain can relax. Module 6 is more hands-on: audits and safety. Walking around with a checklist, scoring areas, finding hazards, and keeping your workplace clean and safe. No math required. Just eyes and a checklist.

Continue to Module 6: Audits & Safety →

← Back to The Long Start · Module 5 of 10 · ← Module 4

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