# Custom software or off the shelf — the honest test

> The shelf wins when the process is standard. Custom wins when the process is the advantage. The expensive mistake is buying custom to do something a plugin already does, or bending a business to fit a tool it has outgrown.

The right question is not 'which is better' but 'is this process generic'. Invoicing, email, calendars, standard e-commerce — a thousand companies do them the same way, which is exactly why the shelf product is cheap and good: the cost of its development is divided by everyone who buys it. Buying standard tooling for a standard process is not compromise, it is arbitrage.

Custom earns its price where the process is the moat: the quoting logic nobody else uses, the workflow that took ten years to get right, the integration between systems that were never meant to talk. There the shelf option costs differently — not in licence fees but in workarounds, exports to Excel, and the person whose job is stitching the gap. When the workaround has a salary, custom is often the cheaper line.

## The three-question test

Would a competitor using the same tool erase your advantage? Then shelf is fine. Does the process change how you win work? Then it deserves custom. And the tiebreaker: count the workarounds — if staff maintain spreadsheets beside the tool, you are already paying for custom, just not getting it.

## The hidden bill on the shelf side

Licence fees are the visible line; the invisible ones are per-seat pricing that punishes growth, plugins that charge monthly for a checkbox, the migration when the vendor pivots, and the features you adapt your process to rather than the reverse. Total cost of the shelf is measured over years, not at checkout.

## The honest case for buying anyway

Sometimes custom is still wrong: when the process is undifferentiated, when nobody will own the result internally, or when the budget buys a bad custom job instead of a good shelf one. Custom done poorly is the worst of both worlds — the licence price plus the maintenance.

## What to take away

- Standard process → shelf; differentiating process → custom.
- Count the workarounds — a spreadsheet beside the tool is already a custom-software bill.
- Shelf TCO is measured in years: seats, plugins, pivots, process-bending.
- Bad custom is worse than good shelf — budget decides which you can afford.

## Tags

Buying software, Build vs buy, TCO

## We build this for clients

https://dfieldsolutions.com/en/services/full-stack

## More from the lab

- https://dfieldsolutions.com/en/lab/custom-software-cost.md — What custom software actually costs
- https://dfieldsolutions.com/en/lab/first-90-days-retainer.md — The first ninety days of a retainer, as it actually goes
- https://dfieldsolutions.com/en/lab/client-portal-vs-email.md — Why clients get a progress page instead of status emails
- https://dfieldsolutions.com/en/lab/checkout-friction.md — Where the checkout loses the sale

---

Source: https://dfieldsolutions.com/en/lab/custom-vs-off-the-shelf
DField Solutions — Dunakeszi, Hungary — dezso@dfieldsolutions.com
Booking: see https://dfieldsolutions.com/en/contact