Agencies often get stuck in a service loop where retainers cap margins at 30...

https://wiki-saloon.win/index.php/How_to_Separate_Client_Delivery_from_Product_Development_Without_Blowing_Up_Your_Agency

Agencies often get stuck in a service loop where retainers cap margins at 30 percent. Start treating your team like a lab to build software instead. Once you turn your internal workflows into a tool, those margins can jump to 70 percent plus.