Most businesses that ask for custom software don't actually need it — a well-configured, proven tool does the job for less money and less risk.
The honest signal is friction: are you working around the software's assumptions every single day, or just occasionally? Occasional friction is a training problem. Daily friction is a fit problem.
When it's genuinely worth it — a process no off-the-shelf tool models correctly, a scale or permission structure nothing else supports — the engineering discipline that goes into it matters more than the fact that it's custom at all.
We say so either way. Most of the time the honest recommendation is a lightweight, connected system built on a proven base, not a ground-up build — and we'd rather tell you that than sell the bigger project.