When to use Kubernetes vs Approle authmethod

Hi Team, I am quite newbie and still exploring hashicorp vault for storing my k8s secrets. I could see documentation stating below two methods to authenticate your target kubernetes cluster( from which, k8s resource like deployment would connect to my seperate dedicated Vault k8s cluster to retrieve secret)

  1. Kuberentes authentication method
  2. appRole authentication method

Can someone advise which out of these two methods should be used under which consideration/scenarios?