🎯 Agile Estimation: The Pizza Party Planning Method
Imagine you and your friends are planning the biggest pizza party ever. How do you figure out how much work it takes to make it happen?
🍕 The Big Idea: Measuring Work Without a Stopwatch
Have you ever tried to guess how long it takes to clean your room? Sometimes it takes 10 minutes. Sometimes it takes an hour. It depends on how messy it is!
Agile estimation is like that, but smarter. Instead of guessing time, we compare tasks to each other. It’s like saying:
“Cleaning my desk is easy. Cleaning the whole room is medium. Cleaning the entire house is hard.”
This works because our brains are GREAT at comparing things!
📍 Story Points: Your Magic Measuring Sticks
What Are Story Points?
Think of Story Points like sizes of pizza slices:
| Size | Points | Example Task |
|---|---|---|
| 🍕 Tiny | 1 | Set up plates on the table |
| 🍕🍕 Small | 2 | Order pizza online |
| 🍕🍕🍕 Medium | 3 | Make the guest list |
| 🍕🍕🍕🍕🍕 Large | 5 | Decorate the whole room |
| 🍕🍕🍕🍕🍕🍕🍕🍕 Huge | 8 | Cook pizza from scratch |
Key insight: Story Points don’t measure hours. They measure effort, complexity, and uncertainty.
Why Not Just Use Hours?
Here’s the secret: People are terrible at guessing time, but amazing at comparing things!
Ask a kid: “How long will it take to draw a picture?”
- Kid: “Umm… 5 minutes? 2 hours? I don’t know!”
Ask the same kid: “Is drawing a house harder or easier than drawing a stick figure?”
- Kid: “Drawing a house is harder!”
That’s Story Points! We compare, we don’t predict time.
Real Example
Your team needs to build a website. Here’s how you might score tasks:
| Task | Story Points | Why? |
|---|---|---|
| Add a button | 1 | Super simple |
| Create login page | 5 | Medium complexity |
| Build payment system | 13 | Very complex, lots of parts |
🏃 Velocity: Your Team’s Superpower Speed
What Is Velocity?
Velocity is how many Story Points your team can finish in one sprint (usually 2 weeks).
Think of it like this:
If your soccer team always scores about 3 goals per game, you can predict they’ll probably score around 3 goals next game too!
How It Works
graph TD A["Sprint 1: 20 points done"] --> D["Average Velocity"] B["Sprint 2: 22 points done"] --> D C["Sprint 3: 18 points done"] --> D D --> E["≈ 20 points per sprint"] E --> F["Plan next sprint: ~20 points"]
Simple Example
Your pizza party planning team completed:
- Week 1: 15 points of work
- Week 2: 17 points of work
- Week 3: 13 points of work
Average Velocity = (15 + 17 + 13) ÷ 3 = 15 points per week
Now you know: “We can probably do about 15 points of work next week!”
Why Velocity Matters
✅ Helps you plan realistically ✅ Shows if you’re improving over time ✅ Stops you from promising too much
Warning: Never compare velocities between different teams! It’s like comparing how fast a fish swims vs. how fast a bird flies. Different teams, different scales.
🃏 Planning Poker: The Fun Estimation Game
What Is Planning Poker?
Planning Poker is a game where everyone on the team guesses Story Points at the SAME TIME using cards.
Why at the same time? So nobody copies someone else’s answer!
The Cards
Most teams use these numbers (based on Fibonacci):
1️⃣ 2️⃣ 3️⃣ 5️⃣ 8️⃣ 1️⃣3️⃣ 2️⃣1️⃣
Why these weird numbers? Because the bigger a task, the harder it is to be precise. The gaps get bigger on purpose!
How to Play
graph TD A["📋 Read the task aloud"] --> B["🤔 Everyone thinks quietly"] B --> C["3, 2, 1... REVEAL!"] C --> D{Do cards match?} D -->|Yes!| E["✅ Use that number"] D -->|No!| F["🗣️ Discuss differences"] F --> G["Play again"] G --> C
Example Round
Task: “Add a search bar to our website”
- 👧 Sarah plays: 3
- 👦 Mike plays: 8
- 👩 Emma plays: 3
Mike explains: “I think it’s hard because we need to search through lots of data!”
Sarah explains: “We already have a search library. We just plug it in!”
After discussion: Everyone agrees it’s a 3 because of the existing library.
Why This Works
🧠 Wisdom of the crowd: Multiple opinions are better than one 🔍 Reveals hidden info: Someone might know something others don’t 🎯 Reduces bias: No one can influence others before they vote
⚖️ Relative Estimation: The Comparison Game
What Is Relative Estimation?
Instead of asking “How big is this?”, we ask “Is this bigger or smaller than that?”
It’s like sorting your toys by size without using a ruler!
The T-Shirt Method
Many teams use T-shirt sizes:
| Size | Meaning | Example |
|---|---|---|
| XS | Tiny, quick | Fix a typo |
| S | Small, simple | Change a color |
| M | Medium effort | Add a new button with logic |
| L | Large, complex | Build a new feature |
| XL | Huge, needs breaking down | Redesign whole section |
How Relative Estimation Works
graph TD A["Pick a REFERENCE task everyone knows"] --> B["Call it a '3'"] B --> C["New task arrives"] C --> D{Compare to reference} D -->|Smaller| E["Give it 1 or 2"] D -->|Same| F["Give it 3"] D -->|Bigger| G["Give it 5, 8, or 13"]
Real Example
Reference task: “Add a logout button” = 3 points
Now compare new tasks:
| New Task | Comparison | Points |
|---|---|---|
| Change button color | Way easier! | 1 |
| Add password reset | A bit harder | 5 |
| Build user dashboard | Much harder | 13 |
Why Relative Works Better Than Absolute
Our brains evolved to compare things, not measure them precisely:
❌ “This rock weighs… 2.3 kilograms?” (hard!) ✅ “This rock is heavier than that one!” (easy!)
🎮 Putting It All Together
Here’s how a real Agile team uses all four tools:
Step 1: List Your Tasks
- Build homepage
- Create user login
- Add shopping cart
- Set up payment
Step 2: Play Planning Poker
Team plays cards for each task:
- Homepage: 5 points
- Login: 8 points
- Cart: 8 points
- Payment: 13 points
Step 3: Check Your Velocity
Team’s average velocity: 20 points per sprint
Step 4: Plan the Sprint
Total work available: 5 + 8 + 8 + 13 = 34 points
That’s more than 20! So the team picks:
- Homepage (5) + Login (8) + Cart (8) = 21 points ✅
Payment (13 points) goes to the next sprint.
🌟 Remember These Key Ideas
| Tool | What It Does | Think Of It As |
|---|---|---|
| Story Points | Measures effort, not time | Pizza slice sizes |
| Velocity | Tracks team speed | Goals per game |
| Planning Poker | Group estimation game | Card game for fairness |
| Relative Estimation | Compares tasks to each other | Sorting toys by size |
🎉 You Did It!
You now understand how Agile teams estimate work without getting stuck on exact times. The secret is simple:
Compare, don’t calculate. Collaborate, don’t guess alone. Track your speed, plan with confidence!
Next time someone asks “How long will this take?”, you can say:
“Let me compare it to something we’ve done before, check our velocity, and give you a realistic plan!”
That’s the Agile way. 🚀