Every founder asks some version of the same question eventually: should we just buy this off the shelf, or build it ourselves? The honest answer is that SaaS and custom software solve different problems, and the mistake is treating it as a permanent decision instead of a stage-dependent one.
SaaS wins when the workflow is generic. Payroll, basic CRM, ticketing — thousands of companies need the exact same thing, so someone has already built it better and cheaper than you could. Fighting that is a waste of engineering time.
Custom software wins the moment your workflow becomes your competitive advantage. If the way you route orders, score leads, or price a job is actually why customers choose you over a competitor, forcing that logic into someone else's SaaS product usually means bending your business to fit their limitations.
The teams that get burned are the ones who wait too long to make the switch — three years into duct-taping a SaaS tool that was never built for their scale. If your workarounds have workarounds, that's usually the signal.