Ever tried to create a GCP resource and encounter issues such as missing permissions?

Essentially, the 'default application credentials' that your code (or that your IAM user) is using, is lacking the required role assignment. To figure out where the problem might lie, GCP offers a Policy Troubleshooter (right off the IAM and Admin menu).

Here, you can specify the RESOURCE (e.g. the PROJECT itself) - and the permission that you were expecting (or that was listed in your error message).

Simple and powerful!

policy troubleshooter
policy troubleshooter