SEO retainers usually cap your margins around 30 percent because you are tied...

https://dibz.me/blog/why-a-handful-of-european-seo-agencies-stopped-being-agencies-and-1138

SEO retainers usually cap your margins around 30 percent because you are tied to billable hours. When you turn your internal workflows into software, you unlock 70 percent plus margins. It is time to stop trading your time for a paycheck.