Most make-or-buy decisions are made too early, before the critical question has been asked: which process actually sets us apart from the competition, and which one doesn't? Those who skip this end up buying standard software for the wrong process or building custom software for one that doesn't need it.
How to identify those critical processes, why standard software hits its limits precisely there, and what an honest total-cost calculation over the lifecycle reveals: that's what this final part is about.
The 80/20 boundary: where standard wins, where it constrains you
A useful rule of thumb: standard software covers around 80 percent of your requirements. The problem is the remaining 20 percent. They're rarely trivial. They're often exactly the processes that make your business successful.
For everything standardisable outside your core business — accounting, payroll, email — standard software wins hands down. These processes are the same everywhere, regulated, and don't differentiate you from anyone. Building them yourself burns money.
But those 20 percent that make you unique, standard software forces into a foreign, idealised workflow. You adapt to the software — not the other way around. And in doing so, you give up exactly what was your advantage. This is precisely where workarounds and spreadsheets alongside the system emerge: a reliable sign that the process doesn't fit the standard template.
Where those 20 percent lie differs from business to business. Often it's procurement planning and production scheduling, your own quoting or variant logic, a customer portal with specialist business rules, or the integration of several systems into one seamless workflow. What they share: they follow no norm, but your own experience. That's exactly why standard software maps them only with friction.