Proper search engine categorization and placement will help you expand your client base and attract new people to your site, but simply submitting your site and doing nothing else would never be enough of a marketing effort. It's only one aspect of a much larger field of endeavor, namely, Internet Marketing. There are many other facets to marketing your site properly. It's interesting to note that the size of your business may not proportionally reflect where your marketing efforts should be concentrated. Each web site will have its own distinct target market and it's very important to determine what that market is before you begin.
Search engines are just big computer programs.
You need to help these machines categorize and index your web site properly. Provide them with the utmost relevant keywords, site description, content and metatags as possible. It helps the search engine to do its job properly. A big misconception some web site owners make is assuming the search engines have intelligence. That the machines will somehow anticipate what you meant to say about your site and take this into consideration when indexing takes place.