Keyword research is quite possibly the most important part of SEO. Ranking for the right keywords can make or break your website. By researching your market's keyword demand, you can not only learn which terms and phrases to target with SEO, but also learn more about your customers as a whole.
It's not always about getting visitors to your site, but about getting the right kind of visitors. The usefulness of this intelligence cannot be overstated; with keyword research you can predict shifts in demand, respond to changing market conditions, and produce the products, services, and content that web searchers are actively seeking.