You create a new Google Kubernetes Engine (GKE) cluster and want to make sure that...

Creating or upgrading a cluster by specifying the version as latest does not provide automatic upgrades. Enable node auto-upgrades to ensure that the nodes in your cluster are up-to-date with the latest stable version.

https://cloud.google.com/kubernetes-engine/versioning-and-upgrades

Node auto-upgrades help you keep the nodes in your cluster up to date with the cluster master version when your master is updated on your behalf. When you create a new cluster or node pool with Google Cloud Console or the gcloud command, node auto-upgrade is enabled by default.

Ref: https://cloud.google.com/kubernetes-engine/docs/how-to/node-auto-upgrades