What actually changed

AI-assisted development lowered the cost of writing software, but not the cost of owning it. Maintenance, security, support, and the opportunity cost of your attention are unchanged. That asymmetry is the whole modern build-vs-buy conversation.

Anyone arguing from build cost alone is answering the wrong question. Version one is the cheapest part of any system that lasts.

1. Is this how you compete?

Build what customers would notice you doing differently; buy what they would never inspect. Payroll, email, accounting, ticketing — nobody chooses you because of them. The workflow that makes your business unusual is the one worth owning outright.

2. Are you the awkward shape?

Off-the-shelf products encode assumptions about how work is done. If you fit them, buying is nearly always right. If you find yourself running the business in spreadsheets alongside the tool, you are already paying for custom software — just in salaries and errors instead of engineering.

The spreadsheet beside the SaaS tool is the specification for what you should have built.

3. What does the integration actually cost?

Bought software still has to be configured, integrated, migrated onto, and maintained against vendor changes. Compare total cost honestly and a surprising number of “obvious buys” turn out to be close calls, particularly where the tool sits in the middle of several systems.

4. Who owns the data, and can you leave?

If the workflow generates data you will want to reason over — with AI or otherwise — check that you can get it out in full, continuously, in a usable shape. Vendors who make export slow or partial are charging you a cost that never appears on the invoice.

This question has become sharper as AI features move from novelty to leverage. Data you cannot reach is capability you cannot build.

5. Will anyone maintain it in two years?

Custom software with no owner becomes a liability faster than most teams expect. If you cannot name the person or partner responsible for it eighteen months from now, buy — even where building would be better on every other axis.

The common answer

Buy the commodity layers, build the thin slice that is genuinely yours, and connect them properly. Most companies get this backwards: they build an internal chat tool and buy the system their competitive advantage runs through.