I agree that only conversions matter, but you should be able to track whether a customer originated from an ad click vs. SEO, whether they clicked one ad and had 4 sessions since, etc.
While it's not a perfect system, you should know with a reasonable degree of accuracy how many dollars you get back for every dollar you put in to ad spend.
As far as the SEO traffic issue, this can also be accounted for once you have scaled your ads beyond the levels of what SEO could yield. At low budgets this can be more of an issue, at high budgets much less so.
While it's not a perfect system, you should know with a reasonable degree of accuracy how many dollars you get back for every dollar you put in to ad spend.
As far as the SEO traffic issue, this can also be accounted for once you have scaled your ads beyond the levels of what SEO could yield. At low budgets this can be more of an issue, at high budgets much less so.