Recently deployed a SharePoint 2016 Farm into a Dev environment, which consisted of a 2x Web Front Ends, 1x Central Administration and 2x Application servers.
Deployed a new Web Application. Went to the Web Front End server and tried to access the new Web App and got prompted for user credentials.
The user logged into the server has Site Collection Admins permissions to the new Web App.

Authenticated using the credentials, but for end users this will be a major pain, as well as not getting
The reason this occurs is because the URL isn’t being classified in the Intranet Zone.
To check, go to the URL. Select File from the Internet Explorer menu then click Properties.

If the File menu is hidden, right click on the internet explorer banner and click File Menu.
You can see below under Zone that it is sitting in Trusted Sites zone.

Resolution:
In Group Policy, navigate to User Configuration > Policies > Administrative Templates > Windows Components > Internet Explorer > Internet Explorer Control Panel > Security Page.
Edit the Site to Zone Assignment List and add the URL into the list and set the zone as 1.
Then click ok.
By default it takes about 90 minutes for the Group Policy to be updated on the clients.
To verify, repeat the above process and confirm that the zone sits in the Intranet zone.
