Search engines still account for a large slice of traffic on the Internet, with most of that traffic pre-qualified and intent driven. Therefore, if you can get your website on the top of search results using search engine optimization you will increase generated leads and conversions.
SEO is a constantly evolving field as search engines tweak their algorithms. Contrary to popular belief SEO is not only about keywords. For instance, Google takes into account more than 200 data points to decide the rank of your website.