Pausing reconciliation of an object comes in handy in many scenarios that require manual intervention. Cluster API resources widely support this feature, as does the CAPI control plane provider for Kamaji, and I would like it to be added here as well.

See related user story from Cluster API: kubernetes-sigs/cluster-api#1780

Other resources in our stack, suck as HelmRelease, also have supported this for a while but chose a different approach than Cluster API: fluxcd/helm-controller#9

One of the big differences between using the spec vs an annotation is that a spec change will increase the generation. This state change might not be ideal in some scenarios, so an annotation would be preferable then.