SEO isn’t necessarily a hard task. While anyone can learn the basics, how you apply the knowledge is what makes the difference between a professional and a newbie. This experience is normally what you pay for because a professional knows exactly how to adjust different strategies to work for a project.
Apart from the actual experience, SEO is also time consuming. If you expect to see results overnight, you’re in for a big disappointment. Apart from time, it also requires a great deal of effort, as well as persistence. Knowing how search engines work is also part of the game.