Will the user click your advertisement?
The chances of user clicking on the sponsored advertisements is much less than organic ones. With the help of SEO, one can generate organic results which have more chances of being noticed and used by the users. This happens because the users develop the trust which sponsored advertisements does not provide in equal degree. Many users have trained their eyes to ignore the spaces on the page where advertisements are displayed.
Cost of following the techniques:
Because SEO involves lot of methods that have to be followed, the cost of following this technique can prove to be a little expensive. It depends on the size of the business along with other factors whether SEO is suitable or not. But if you can invest, SEO is worth it. As far as PPC is concerned, it is good for those who are limited on budget and have a clear statistics in mind as to how many leads they want in how much budget. You can set aside a daily maximum limit and get the leads accordingly.