Most SEO retainers cap your margins at 30 percent because you’re trapped by...

https://bizzmarkblog.com/what-mistakes-do-agencies-make-when-they-try-to-ship-software/

Most SEO retainers cap your margins at 30 percent because you’re trapped by labor costs. If you turn your internal workflows into repeatable software, you can hit 70 percent margins and finally scale. Treat your agency like a product lab.