By Hiran de Silva
Earlier today I shared a preview of the Friends Expenses Challenge with a number of people on LinkedIn.
My expectation is simple — and deliberate.
Some will say they don’t have time.
A few honest ones will say they have no idea where to start.
And some, very confidently, may say “this can’t be done in Excel.”
That reaction is the point.
Because this challenge is not really about expenses.
It’s about a misunderstanding that sits at the heart of how Excel is taught, discussed, and judged in business.
The Core Criticism of Excel in the Enterprise
The loudest and most persistent criticism of Excel — from IT departments, technology strategists, and the Excel-replacement / FP&A tools industry — is always the same:
- Excel is not scalable
- Excel has no reach
- Excel does not support collaboration
- Excel cannot consolidate
- Excel lacks security, governance, and control
And if Excel means “a single spreadsheet emailed around” — they are absolutely right.
But that definition of Excel describes only one world.
The Two Worlds of Excel
Excel lives in two completely different worlds, inside the same software.
World 1 — The Left-Hand Box (Saturated)
This is the world nearly all Excel training is designed for:
- One user
- One spreadsheet
- One machine
- An isolated task
- Often ad-hoc
- The creator is also the customer
This is the world of:
- Social-media Excel tips
- YouTube tutorials
- Online courses
- Books
- Webinars
- Competitions
Even elite events like the Microsoft Excel World Championship test exactly this scenario:
an individual solving a one-off problem in isolation.
This world is saturated. Overflowing.
World 2 — The Right-Hand Box (Empty)
This is the world of real work.
- Many users
- Many spreadsheets
- Many machines
- Multiple departments
- Ongoing processes
- Continuous operation
- Real accountability
Here, spreadsheets are not personal tools — they are components in an end-to-end business process.
This is the world finance leaders actually live in.
And here’s the problem:
👉 There is almost no training, guidance, or acknowledgment that this world even exists.
The Driving Analogy
Think of it like driving.
On private land, you can drive however you like:
- No licence required
- No rules
- No consequences beyond yourself
That’s World 1.
You are the customer.
You decide whether it works.
Nothing breaks beyond your own task.
But the moment you drive on a public highway:
- Other people matter
- Rules matter
- Purpose matters
- Competence matters
You might be driving:
- A delivery van
- An ambulance
- A work vehicle
- A commuter route
You are no longer driving for pleasure.
You are part of a system.
That’s World 2.
And yet almost all Excel education trains people only for the car park — then sends them onto the motorway and blames Excel when things go wrong.
From a Fun Puzzle to an Enterprise Process
The original inspiration for this demo comes from a Christmas expenses challenge shared by Oz du Soleil, later refined by Miguel Escobar.
That challenge is a World 1 problem:
- A small group
- A finite set of expenses
- A one-off reconciliation
- End of story
Perfectly valid. Perfectly fun.
But it is not enterprise work.
The Friends Expenses Challenge (Reframed)
So I reframed it.
Instead of three siblings, we now have six friends — Chandler, Monica, Ross, Rachel, Joey, and Phoebe — from Friends, living in New York and planning a trip to London.
Now the requirements change completely.
Level 1 — Ongoing Reconciliation
After 40 expense claims, who owes whom what?
Level 2 — Continuous Operation
This system doesn’t end after the trip.
Expenses continue indefinitely.
Level 3 — Unattended Automation
No one should be “working” the spreadsheet.
The logic must be embedded in the model.
Level 4 — Distributed Users
Different computers.
Different locations.
Different time zones.
Everyone must see their position at any moment, just like a banking app.
Level 5 — Scalability
Not 6 friends.
What about 600?
What about 6,000?
Level 6 — Governance
Authentication.
Validation.
Abuse prevention.
These are enterprise requirements.
“That Can’t Be Done in Excel”
Many people will say that.
And that reaction reveals something important.
Because the solution does exist — and it works:
- No formulas
- No Power Query
- No dynamic arrays
- No LAMBDA
- No XLOOKUP
- No Excel tables
- No Python
- No trending features
A database exists — but it only stores data.
It does not “do the work”.
Excel drives the process.
So the real question is not whether it can be done.
The real questions are:
- Who teaches this way of thinking?
- Where does anyone learn this?
- Why is this mindset missing?
Literal Learning vs Lateral Thinking
What’s missing is not a feature.
It’s a mindset.
Most Excel education is literal:
“Here’s what’s on the ribbon.
Here’s what you can click.
Here’s what you can demonstrate on screen.”
Enterprise Excel requires lateral thinking:
- Process first
- Architecture first
- Data flow, not paper flow
- Design for people you will never meet
This is exactly the kind of thinking finance leaders want — and almost never see.
Why This Matters
When finance leaders see this kind of solution, something changes.
They realise:
- They don’t need £10–£50 million systems
- They don’t need long ERP implementations
- They don’t need to abandon Excel
They need better architectural thinking.
And people who can think like this?
They are worth three times more than a typical “Excel expert”.
The Real Question
So I’ll end where I began.
This isn’t about Friends.
It isn’t about expenses.
And it certainly isn’t about showing off.
It’s about asking:
Why is this entire world of Excel missing from education?
Where can anyone learn this way of thinking?
And why are finance leaders forced to believe Excel is the problem — when it’s actually the training?
That’s the real challenge.
Add comment