Mostly, it is the boring stuff
Not dramatic architectural waste. A disk nobody unplugged, a test server nobody switched off, a tier somebody picked two years ago. It adds up quietly and nobody has time to go looking.
A disk that is not plugged into anything
Storage bills for the space it reserves, whether or not anything can reach it. These usually outlive the server they were built for.
A server that is switched on but doing nothing
It still bills the full hourly rate. Shutting it down stops the charge and keeps the disks, so it starts again exactly as it was.
Test servers running nights and weekends
Nobody works those hours but the meter does. A machine only needed in office hours bills for roughly three times what it is used.
A server bigger than the work it does
Machines get sized on a guess before launch and nobody goes back. One size down usually costs about half.
A reserved internet address attached to nothing
Delete a server and its address often stays behind. Azure charges to hold it whether anything answers on it or not.
Old backups of disks that no longer exist
Snapshots are taken before a risky change and then forgotten. They keep billing long after the thing they protected is gone.
4 of these run out of the box
3 of those it fixes by itself. Everything else stays switched off until you turn it on, because software that deletes things should be a decision you made rather than a default you inherited.
See what it would changeIt also looks for:
server on older hardware than Azure offers today · outbound gateway with nothing routed through it · traffic router pointing at nothing · ExpressRoute circuit billing with no carrier connection · Front Door profile with no endpoints · Front Door Premium without a Premium-only feature configured · HDInsight worker nodes without autoscale · NetApp capacity pool larger than its volumes need · SQL Managed Instance without Azure Hybrid Benefit · web hosting plan with no websites on it · web hosting plan bigger than its traffic · web hosting plan on a pricier tier than it needs · Always-on capacity for code that rarely runs · staging copy of a site nobody visits · AKS paid control plane on a non-production cluster · Redis cache with no clients and no lookups · Premium container registry on a non-production registry · PostgreSQL flexible server nothing connects to · MySQL flexible server nothing connects to · AI Search service nothing queries · Dedicated SQL pool online with nothing querying it · Serverless SQL database with auto-pause switched off and nothing using it · Data Explorer cluster running idle that will never stop itself · Machine Learning compute instance with no automatic stop · Analysis Services server running with no queries and no processing · Gallery image version past its end-of-life date, still replicated · SQL Server VM paying the Azure licence rate · Windows VM paying the Azure licence rate · Premium SSD paying to burst and never bursting · Container group running and talking to nobody · SignalR service nobody connects to · SignalR units bought far above the observed peak · Dedicated host with nothing placed on it · DDoS Network Protection plan attached to nothing · Zone redundancy on a non-production SQL database · Container App holding replicas warm with no traffic · Cosmos DB account nothing queries · Hot-tier blob data that nothing has touched · PostgreSQL flexible server billing for backup beyond its free allowance · MySQL flexible server billing for backup beyond its free allowance · Non-production backup vault on geo-redundant storage · Backup item whose source resource no longer exists · fast disk on a machine too small to use the speed · Premium disk on a VM that has been off all window · disk on an older storage tier · File transfer switched on but never used · Geo-redundant storage account outside production · load balancer with nothing behind it · private connection to something that is gone · remote access service nobody logs in through · firewall on the expensive tier without the expensive features · Azure Firewall that has processed no traffic · VPN gateway with nothing connected to it · ExpressRoute gateway with no circuit connected to it · API Management service nothing is calling · Service Bus namespace nothing is sending to · Event Hubs namespace nothing is publishing to · server on the wrong type of machine · server group kept larger than its traffic needs · shared database pool with no databases in it · test database on the top-tier plan · SQL Database or elastic pool without Azure Hybrid Benefit · Reserved AI capacity you are not using · Reserved AI capacity on a test workload · Logs kept far longer than anyone looks at them · Log Analytics workspace retained beyond the free period · Managed HSM pool on a non-production resource · Zone-redundant Elastic SAN outside production · Fabric capacity left running outside production · VMware private cloud outside production · Public IP prefix with nothing allocated from it · ExpressRoute Direct port with no circuit on it