To maintain quality search results, search engines frequently change their ranking algorithms. The continuous changes prevent hucksters and unsavory sites from appearing in searches in which they do not belong. If you do not pay attention to the changes, your site will gradually decline in the rankings. It goes without saying that if your competition does pay attention, their rankings will improve. Another consideration is the fact that search engines are growing rapidly.
Sites periodically disappear from search engine listings.
Unfortunately, it takes time to get back into a search engine once the site disappears. A search engine maintenance plan with a reliable Web consulting firm will insure that your site is monitored and optimized for current search engine algorithms.