SEO retainers usually cap your profit margins at 30 percent no matter how well...

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

SEO retainers usually cap your profit margins at 30 percent no matter how well you scale. Try treating your agency like a lab to productize your internal workflows. Shifting to software is the easiest way to push those margins past 70 percent.