Why Kubernetes Cost Tools Fail for Multi-Tenant Clusters

Multi-tenant clusters are efficient until you cannot prove who spent what. Most tools fail because they assume perfect metadata and ignore shared services.

• Missing labels: no owner/team on workloads → unallocatable spend.
• Shared controllers: ingress, mesh, and logging spread unevenly without policy.
• Quota drift: tenants grab more CPU/memory over time; no guardrails to stop them.
• Egress blindness: cross-AZ and internet traffic aren’t tied to owners.
• LB/NAT sprawl: each tenant spawning its own LBs/NATs multiplies fixed costs.
• No expirations: temporary quota bumps never roll back; waste becomes the default.

Fix it with enforced labels, ResourceQuota/LimitRange per namespace, shared-service allocation rules, and a cost agent that exports per-tenant burn rate. Then the bill stops being a blame game.***