Do You Need Custom Software, or Will a Spreadsheet Do?

Spreadsheets are wildly underrated. Businesses turning over crores run on them. Before anyone builds you software, it is worth being honest about whether you need it.

When a spreadsheet is the right answer

• One person uses it. No conflicts, no permissions, no confusion.
• The process is still changing. A spreadsheet takes seconds to restructure; software takes a change request.
• Under a few thousand rows. Modern spreadsheets handle far more than people assume.
• You need it working today.

If all four are true, do not let anyone sell you an app. Improve the spreadsheet.

Five signs the spreadsheet has stopped working

1. Two people are editing it and overwriting each other

The moment more than one person needs to update the same data at the same time, you are fighting the tool. Shared spreadsheets help; they do not solve it. Version conflicts, accidental deletions and "who changed this?" become weekly events.

2. You are copying the same data between places

Enquiry arrives → copy to sheet → copy to invoice → copy to WhatsApp → copy to accounts. Every copy is a chance to introduce an error, and it will happen at the worst possible time.

3. Everyone can see everything

Your staff need to update bookings. They do not need salary data, supplier costs or the full customer list on their phone. Spreadsheets have no meaningful per-row permissions.

4. Rules only exist in someone's head

"Never book two slots for the same trainer." "Always check stock before confirming." Software enforces rules. A spreadsheet just watches you break them.

5. Customers should be doing the data entry

This is the big one. When customers can book their own slot, check their own order or submit their own details, a whole category of work disappears. A spreadsheet cannot safely be handed to a customer.

If two or more of these apply, custom software has probably become cheaper than the spreadsheet.

What "custom software" costs now

This is what has changed. Building a small internal tool used to mean months and a budget that only mid-sized companies could justify. AI-assisted development has cut the build time on straightforward business tools substantially — which moves the break-even point down to businesses with ten staff rather than a hundred.

A focused tool — one that does bookings, or quotations, or stock, well — is now a matter of weeks rather than quarters. That is the genuine shift. Not that software got magical, but that the boring parts of building it got faster.

Build small, and build the right small

The most common failure is scope. Someone asks for "a system to run the business" and gets an eighteen-month project that is obsolete before it launches.

The pattern that works:

1. Pick the single worst process. The one that causes the most rework or the most arguments.
2. Build only that. One tool, one job, used daily.
3. Live with it for a month. You will discover things no requirements document would have caught.
4. Then extend it, or build the next one beside it.

A business with three small tools that each do one job well is in a far better position than one waiting on a monolithic system.

Questions to ask before anyone builds anything

• Who owns the code? The answer should be you. Get it in writing.
• Where does the data live, and can I export it? If the answer is vague, walk away.
• What happens if you disappear? Any competent developer should be able to pick it up. That means documentation and standard technology, not something exotic.
• What does it cost to run? Hosting and maintenance, monthly, in writing.
• Can it be changed later, and at what rate? Your process will change. The software has to.

And when off-the-shelf is right

Do not build what you can buy. Accounting, payroll and GST filing are solved problems with mature, cheap, compliant products. Building your own is almost always a mistake.

Custom is for the part of your business that is genuinely yours — the way you quote, schedule, or track the thing you actually sell. That is where off-the-shelf software makes you work its way instead of yours, and where a small custom tool pays back fastest.

The short version

Stay on the spreadsheet as long as it works. When two people are fighting over it, when you are copying data between systems, or when customers should be entering their own information — that is the moment. Then build the smallest useful thing, and only extend it once you have used it.