Is it true that once you obtained the first position in the organic results, you can stop paying for that keyword in Adwords?
Most would say yes, but the reality is that the searcher isn't specifically searching for your website. He´s just searching for what's in your website. The problem is that he can probably find it in a bunch of other websites too, and those websites show up too in the organic results and the paid results.
In the end, what matters is cost per conversion. Once you have obtained top positions in the organic results, the costs per conversion will drop significantly while the costs per conversion from paid results will remain the same. That seems to say: Stop Paying for Adwords! But is that really the smart thing to do?
The reality is that cost per conversion isn't really the end. The real end is the overal profit you make, and if Adwords can add 20% to the over all profit, then there's no reason to stop using Adwords. Even if it means that your profit per sale on adwords related sales is a bit lower. Of course, if those additional sales end up in having to increase capacity and with that the cost per product (at least in the beginning), then you may want to consider not using Adwords. Overall profit is what makes the decision.
2 links in the SERP (organic + PPC) increases the chances your link is clicked on. Taking one of those links out, automatically means the chance somebody will visit your site reduces as well. That is because for a given SERP, there are so many searches done and so many clicks available. These clicks are devided over all links in the SERP (Organic + PPC). People won't stop clicking PPC links when your site isn't showing there anymore.
So do you really want to stop paying for Adword clicks once you reached your
SEO goals?