The problem with cramming too many keywords on your home page is that they encompass a too big of a span theme wise for the search engine spiders to see your site as specific. Individually they can never get the keyword density or repetitions need to order the site highly. When it comes to SEO keep your keywords short, sweet yet targeted for best results. If you load it with popular, generic or “most visited” terms you are going to end up with a lot of visits from people on the internet who are not intent on buying a thing.
The solution to this is to focus the content on your home page on three to five of your top keywords or key phrases. For instance if you have a site about search engine optimization don’t use keywords like SEO or search engine optimization. You need to find sub keywords that are a little less general such as SEO home page techniques or SEO top keywords to get the attention of targeted visitors. As a rule of thumb the more competitive your site is the less keywords you should choose. Choose only two or three excellent words or phrases and use them three times in each block of text on your site to bring you the most business and try to keep your title copy to less than seven words (but ideally five words!)