Dear Stakeholder: Here’s Why I’m Giving You a Range Instead of a Date
I love writing down my thoughts in form of a letter. When I went through my Certified Agile Leadership course I remember that we had to create an artifact and I wrote a letter to my own Ego, one of the most intimate things I have ever written.
So this time it is not as personal and yet I wanted to address the stakeholder.
Not as a manifesto, not as a lecture, but as an honest letter.
Because I’ve had this conversation dozens of times now, and I think it deserves to be written down.
If you’re a stakeholder, a product manager, a department head, a CEO, someone who needs to know when something will be delivered, this is for you. And I mean that genuinely: for you, not at you.
Dear Stakeholder,
I owe you an apology.
Not for what I’m about to tell you, but for what I’ve been telling you for years. What we’ve all been telling you. What this entire industry has been telling you.
We’ve been lying to you. Not maliciously. Not even consciously, most of the time. But lying nonetheless.
Here’s what we’ve been doing. You ask us when something will be done. We go into a room. We talk about it for an hour or two, sometimes longer, it might even take us weeks.
Someone says “feels like a 5.”
Someone else says “I’d say 8.”
We discuss, we negotiate, we converge on a number.
Then we add those numbers up, do some math with a thing called velocity or capacity planning, and out comes a date.
June 12th.
It goes on the roadmap. It goes in the board deck. It goes in the quarterly plan.
Other teams plan their work around it.
Marketing schedules a launch.
Sales starts making promises.
An entire chain of commitments is built on top of that date.
And here’s what that date actually is: it’s the output of a group of people guessing, influenced by whoever spoke first, anchored to whatever number was mentioned earliest, shaped by optimism, and pressured by the unspoken knowledge that saying “we don’t really know” is not an acceptable answer in that room.
Being completely honest with you, it is build on a lot of half-truths and lies.
That’s what we built the plan on. That’s what you built your plan on.
And I’m sorry, because I was in that room, and I didn’t say anything either.
Do you still remember the last time a date we gave you actually held?
I’m asking honestly. Because when I think back, I struggle to find one.
And I’ve been doing this for a long time.
June 12th comes and goes. It’s not done.
There’s a perfectly reasonable explanation, there always is.
A dependency we didn’t see. A technical complexity that only became visible once we started. Someone was sick for two weeks. Public Holidays come out of nowhere. The Summer was unexpectedly nice. Another team didn’t deliver what we needed when we needed it. All true. All legitimate. All completely predictable in hindsight, because these things always happen. They happen on every project, every time. And yet, every time, the estimate is made as if this time they won’t.
The new date is June 26th. Then July 10th. Then “end of July.” Then Q3.
I’ve watched this cycle play out dozens of times. In different companies, different industries, different team sizes. The details change. The pattern doesn’t. And for the longest time, I thought the answer was to get better at estimating. Better techniques, more buffer, better workshops, better spreadsheets.
If we just tried harder, the dates would hold.
They didn’t.
And here’s the part that took me too long to accept: the date was never real.
It was never based on evidence of what was likely to happen.
It was based on a story about what we hoped would happen. And we told that story with such confidence, with specific dates, with decimal points, with colour-coded Gantt charts, that it felt like a fact.
But confidence is not the same as accuracy. And a plan built on unreliable dates is not a plan. It’s a shared fiction that everyone agrees not to question until reality makes it impossible to ignore and that is usually when it is too late.
I know that’s hard to hear. It was hard for me to accept, too. Because it means that all those roadmaps, all those quarterly plans, all those commitments we made with such certainty, they were built on sand. And we all knew it, somewhere, but nobody wanted to be the person to say it out loud.
So here I am, saying it out loud.
The way we’ve been predicting delivery doesn’t work. It has never worked.
And I don’t think trying harder at the same approach will change that, because the problem isn’t effort or skill. It’s that human beings are simply not built for this kind of prediction. We’re too optimistic. We anchor on the first number we hear. And here’s the part that really got to me when I first understood it: we’re inconsistent. The same team, given the same work, on a different day, in a different mood, would give you a completely different estimate. And no amount of planning will fix this.
Your roadmap isn’t just optimistically wrong. It’s randomly wrong. And nobody has been telling you that.
But I’m telling you now. And I’m also telling you that there’s something else we can try.
I’m not going to give you a date anymore. I’m going to give you something like:
“There’s an 85% chance we’ll be done by June 20th. There’s a 50% chance we’ll be done by June 6th.”
I know. It’s not what you’re used to. It doesn’t fit neatly into a Gantt chart. Your board might look at you funny the first time you present it this way. I get it. I really do.
But let me tell you what you’re actually getting.
You’re getting an honest answer. One that doesn’t pretend certainty where there is none. One that shows you the range of what’s likely and lets you decide how much risk to take. If you need to commit to something externally, use the 85% date and sleep well. If you’re planning internally and can absorb some uncertainty, the 50% date gives you an earlier target. That’s not less information. That’s more. That something that helps you make better decisions.
These numbers don’t come from a meeting where people raised their hands and guessed.
They come from our organization’s actual historical data.
How many things we really complete per week.
We run thousands of simulated scenarios based on that, and the result is a probability distribution. It’s not a crystal ball. But it’s dramatically more reliable than what we’ve been doing.
And something changes in the conversations, too.
Instead of “are we on track?” which, let’s be honest, is a yes-or-no trap that nobody wants to answer honestly, the conversation becomes: “how has the probability changed since last week, and what’s driving it?”
That’s a question that leads somewhere. That’s a question that actually helps both of us.
I’m not asking you to lower your expectations.
I’m asking you to raise them, for the quality of information you accept. Because you’ve been settling for false precision dressed up as certainty, and you deserve better than that.
A single date is the delivery prediction equivalent of “trust me.”
A range with probabilities is the equivalent of showing our work.
I think you deserve the latter. I think we both do.
So the next time I give you a range instead of a date, know that it’s not because I don’t have an answer.
It’s because I finally have a better one.
And I respect you too much to keep giving you the old one.
Let’s try this. That’s all I’m asking. Let’s try.
With respect and transparency,
Peter
P.S. Did you know that an 85% confidence level means there’s still a 15% chance we won’t make it?
I know that sounds uncomfortable.
But isn’t it better to know that upfront than to find out on the day it was supposed to be done?
Why I Wrote This
If you’ve read this far, you’re probably either a stakeholder who recognized something uncomfortable in those paragraphs, or someone who’s been trying to have this conversation for a long time. Or you just waited for something insane to happen in this letter.
For the stakeholders: I’ve worked with many of you, and the vast majority don’t actually want a false date.
You want confidence.
You want to know if something is at risk early enough to do something about it. Probabilistic forecasting gives you exactly that, but it requires letting go of the illusion that a single date ever provided it.
For the delivery people: I know this conversation takes courage. It’s scary to say “I’m going to give you a range” when everyone else in the organization is giving dates.
But in my experience, once stakeholders see how much more useful probability-based information is, once they experience a quarter where they weren’t blindsided, they don’t want to go back.
The hard part isn’t the math. The hard part is the first conversation.
This letter is my attempt to make that a little easier.
At LetPeopleWork, this is what we do.
With Lighthouse, our open-source forecasting tool, we make these forecasts possible from your Jira or Azure DevOps data. But the tool is the easy bit.
The harder part is the human part. The conversation part. The part where someone has to look a stakeholder in the eye and say: “The way we’ve been doing this doesn’t work. Here’s something better.”
If you want to try this in your own organization, feel free to share this letter.
Print it out. Put it on someone’s desk. Start the conversation.
And if you want help with what comes after that conversation, we’d love to hear from you.
Peter Zylka-Greger is co-founder of LetPeopleWork GmbH and the co-creator of Lighthouse, an open-source Monte Carlo forecasting tool for agile teams. He writes about flow metrics, organizational development, and the human side of delivery at letpeople.work.