AWS Lake Formation
Developer Guide

Step 7: Clean Up Existing IAM Policies

After you set up the AWS Lake Formation permissions and you create and attach the coarse-grained access control AWS Identity and Access Management (IAM) policies, complete the following final step:

By doing this, you ensure that those principals no longer have direct access to the data in Amazon Simple Storage Service (Amazon S3). You can then manage data lake access for those principals entirely through Lake Formation.