When the client base is small
A flat license is spread across your clients. With only a few, the per-client cost stays high and the branding benefit reaches very few people. Firms in that position often do better by recommending software and earning a reseller discount while the practice builds.
The HelloBooks Partner Program is free and offers a reseller discount that grows with your client count, with no branding license. It suits firms that want reliable software for clients without committing to a license, and it leaves room to reconsider white-labeling later.