The most common mistakes in a technology due diligence

On the seller's side, the most common mistake is starting too late. Gathering technical documentation, clarifying code ownership and scheduling interviews with the teams in just a few days, under the pressure of the deal timeline, almost never produces a convincing file. Preparation started several weeks ahead, even a basic one, changes the buyer's perception: it signals a company that knows its own business, rather than one discovering its gaps at the same time as the auditor.

On the buyer's side, the most frequent mistake is focusing on code and architecture while leaving organizational technical debt aside: dependency on a handful of key developers, lack of documentation, a manual and non reproducible deployment process. These risks often weigh more heavily on medium term valuation than a questionable technology choice, precisely because they are hard to fix quickly after the deal closes.

Software quality, security and vendor compliance remain three classic blind spots. An interview with the CTO alone, however competent, is not enough: it reflects one point of view, not a verified state of affairs. Cross referencing answers with documents (contracts, architecture diagrams, security scan results) surfaces gaps that a conversation never reveals on its own.

A shared assessment framework, same domains, same questions, same risk scale, does not eliminate negotiation, but it refocuses it on verifiable findings rather than diverging perceptions. It has a limit, though: it does not replace the sector expertise of a buyer who already knows the risks specific to their market, and on the most sensitive topics it is worth complementing with specialist advice.