The serverless-versus-hosting cost debate is usually too shallow. The real tradeoff is not serverless versus servers, it is utilization efficiency versus economies of scale. Serverless makes waste visible as usage; hosting hides it as idle capacity. The cheapest system is the one whose cost model matches the shape of the workload and the maturity of the team operating it.

Cost-adjusted software engineering judges work by the value it creates against the full cost of building and operating it, not just whether it shipped. You can pay up front through testing, CI/CD, and clear ownership, or pay forever through incidents and rework.