What costs do build-vs-buy spreadsheets usually miss?
Years two through five: maintenance and refresh, dependency and security updates, the salary of the named owner, and the risk cost of that owner leaving. The build is usually the cheap part.
RELATED PAGE · Total Cost of Ownership Does the best-documented insourcing case show cost savings?
No - and that is the honest base rate. Norway's NAV brought 100+ systems in-house successfully, but peer-reviewed researchers could not find clear evidence of the projected savings. The benefits that materialized were ownership, speed, and quality.
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