Cost of Delay: Put a Price on Waiting

Cost of Delay is the value you lose for every week a piece of work isn't live. It turns urgency into a number, so the order of work isn't decided by whoever shouts loudest.

Once a team can see that a feature is worth £8,000 a week, the conversation about what to do next changes completely.

The Origins of Cost of Delay

Donald Reinertsen made the case for it in The Principles of Product Development Flow. His argument was that most organisations track cost and efficiency closely but never put a value on time. If you only quantify one thing, he suggested, quantify the cost of delay.

The Three Inputs

• Value. What will the work be worth once it's live? Turn that into a weekly figure.
• Urgency. How does the value change over time? Does it fade, stay steady or only start on a fixed date?
• Information value. What would it be worth to find out early that this is the wrong path?

Urgency Comes in Shapes

Not all delays cost the same. Three common patterns cover most work.

• Steady value. Cost savings often look like this. If you're late, you lose the weeks of savings you missed, but the eventual peak is the same.
• Value from a fixed date. Regulatory work often looks like this. Nothing is gained by delivering early, but being late can be very expensive.
• Value that fades. Seasonal or competitive features look like this. Arrive late and you may never reach the same peak.

Knowing the shape stops you rushing work that can safely wait and protects the work that can't.

When to Choose Cost of Delay

Choose Cost of Delay when everything is urgent and you need to show what waiting really costs. It's especially useful when senior stakeholders are competing for the same team.

How to Calculate Cost of Delay, Step by Step

1. Estimate what the work is worth once it's live. Use the four benefit types: increase revenue, protect revenue, reduce costs and avoid costs.
2. Turn it into a weekly figure. Divide an annual value by 52.
3. Work out the urgency shape. Does value fade, stay steady or start on a fixed date?
4. If there's a fixed date, work back to the latest sensible start.
5. Write down your assumptions. Every figure should have a short reason next to it.
6. Share the number and the assumptions openly.
7. Use it to sequence the work, often by dividing it by duration with CD3.

A Worked Example

A regional bus company has three pieces of work waiting for one digital team.

Work	Value	Shape	Cost of Delay
Contactless top-up in the app	£260,000 a year in extra fares	Steady	£5,000 a week
Accessible timetable changes	£150,000 fine if not live by 1 April	Fixed date	Low now, very high after the deadline
Summer events shuttle booking	£60,000 over one summer	Fades	£5,000 a week, but only from June to August

Without Cost of Delay, the team was going to start with the shuttle, because the events team was loudest. With it, they could see contactless top-up was earning nothing while it waited. They started there, planned the timetable work back from April and scheduled the shuttle to land just before June.

Getting Started When the Numbers Feel Hard

Many teams avoid Cost of Delay because they think they need perfect financial data. They don't. A rough, honest figure is far more useful than no figure at all.

Start with one piece of work that already matters to everyone. Ask what its purpose is. Keep asking why until the answer lands in one of four places: it brings in money, protects money we already have, saves money or avoids a future cost.

Then make a sensible estimate. If a change should keep 200 more customers a year, and each customer is worth £300 a year, that's £60,000 a year, or about £1,150 a week. Write the assumption next to the number.

Ask your finance team for help with the common figures, such as the cost of a role or the value of a typical customer. Keep these in a shared sheet so every team uses the same numbers. That makes comparisons fair.

Show the figure as a range if you're unsure. "Between £800 and £1,500 a week" is still enough to tell you whether this work matters more than the item next to it.

Above all, start. The first figure on the wall changes how people talk about urgency. The second and third come much more easily.

Common Mistakes

• Chasing precision. A sensible range, shown openly, beats a confident number nobody can check.
• Ignoring the shape of urgency. Some work is worth nothing until a set date.
• Hiding the assumptions. When the reasons are visible, people challenge the reasons, not each other.
• Using it once and forgetting it. Revisit the figures as you learn.

How Cost of Delay Compares with Other Tools

Cost of Delay and CD3 go together. Cost of Delay gives the value of waiting. CD3 divides it by duration to give the best order.

Cost of Delay and WSJF share a foundation. WSJF uses relative scores where money is hard to estimate.

Cost of Delay and RICE look at different things. RICE weighs reach and confidence. Cost of Delay weighs time.

In my experience, the first Cost of Delay figure a team puts on the wall does more for prioritisation than any framework slide. People finally see what the queue is costing.

The Product Field Kit includes a fillable Cost of Delay worksheet and a calculator that works out the weekly figure and the total lost to waiting.

Questions People Ask

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