Every cloud migration starts with a business case built on savings: move off aging on-prem hardware, stop paying for capacity you don't use, cut the datacenter lease. Six months later, the invoice tells a different story.
This isn't usually a failure of architecture. It's a failure of governance. Once workloads land in the cloud, teams keep managing them the way they managed a datacenter — provision once, forget about it — instead of treating cloud spend as something that needs continuous attention. The result is predictable: idle compute nobody decommissioned, storage tiers nobody revisited, and a monthly bill that only Finance actually reads, usually after the fact.
Closing that gap is what FinOps — cloud financial management — is built to do. Not as a tool you buy, but as a practice: give the technical team real-time visibility into what they're spending, and make cost part of the same conversation as performance and security, instead of a surprise that shows up in a monthly report.
The upside is larger than most teams expect: once an organization matures from paying for what it might need to paying for what it actually uses, reserved capacity and Savings Plans can cut compute costs by up to 72% compared to on-demand pricing (AWS's published figure for Savings Plans). But that only works once there's real visibility into which workloads are stable enough to commit to.
Treat the migration as step one, not the finish line. The teams that actually see the savings they modeled are the ones who keep optimizing after go-live.