Doing the hard yards to make your site accessible has multiple 'secret' benefits, according to Trenton Moss, over at Sitepoint. As well as better usability:
Web accessibility has so many benefits that I really do wonder why such a large number of Websites have such diabolically bad accessibility. One of the main benefits is increased usability, which, according to usability guru, Jakob Nielsen, can increase the sales/conversion rate of a Website by 100%, and traffic by 150%.
your site will also be more search friendly:
One of the main benefits of Web accessibility is that a Website that's more accessible to people is also usually more accessible to search engines. The more accessible your site is to search engines, the more confidently they can guess what the site's about, giving your site a better chance at the top spot in the search engine rankings.
Both articles contain practical examples (and yet another reason to perfect your descriptive link writing).
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