Answered by Dan Lawrence, SEO and e-commerce specialist
Apart from the obvious (no need to pay for traffic), the entire process really helps you get to grips with the fundamentals of both you website and your proposition and to deal with the foundations of both in a best practice manner.
This usually helps your success/performance across the board, since a well seo'd website will usually achieve better results for all your other marketing activities too, such as paid search ads and better conversion rates since a well SEO'd site will usually be very 'tidy' and clean and provide a highly efficient pathway to the objective, compared to a non seo'd site.
I would certainly deploy paid media as well to test the proposition and how targeted traffic behaves. But always focus on the foundations, and build up from there
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