Cloud cost is an architecture topic, not an accounting one. Five patterns that bloat the bill and the fixes we use in the field.
Visibility first
You cannot cut a cost you cannot measure. The first step is always tagging: tying every resource to a team, environment and service. An untagged cloud account is a bill with no line items.
The five most expensive patterns
Five patterns recur across the field: idle-but-running environments, over-provisioned instances, forgotten snapshots and volumes, cross-region data transfer, and logging. Most bill bloat traces to one of these five.
Architectural decisions
Real savings come from architecture, not small tweaks: serverless versus reserved capacity for the right job, separating hot data from cold storage, actually wiring autoscaling. Set up once correctly, these lower the bill for good.
It is a culture thing
FinOps is not a one-off cleanup but a continuous habit. When you make cost a metric the engineer can see, optimization follows on its own. An invisible cost is always a growing cost.
