To successfully optimize your site and rank well in search engines, you should keep in mind this phrase: Content is King but Links are the Bling.
Rich content, that is optimized correctly, may be all you need to rank well for many non-competitive terms. This is important, as these terms can bring in substantial traffic. However, to rank well for any phrase that is at all competitive, you have to take on the chore of getting backlinks. In some cases, that may mean thousands of backlinks and months of work (unless, of course, you have the budget to pay for them). In today's Google search engine, anchor text is is the only solid path to great rankings.
Create a well-optimized site with good content - but never forget the bling. If you miss out on acquiring lots of backlinks that feature your keywords in the anchor text, you will miss out on tons of traffic.