From the Horses Mouth
Producing information in such a way that all your customers can read makes good business sense, is the law and is fair. Businesses spend £20 billion each year on communicating with their customers. There are two million people with sight problems in the UK who cannot read standard print.
Businesses cannot afford to ignore this large customer group. In addition to making good business sense, companies and organisations are legally required to make reasonable adjustment to provide accessible information or services under the Disability Discrimination Act.
It is a strong case. You will notice that the first point states “good business sense”, followed by a couple of stats and a reminder of the DDA. Accessible standards-compliant web sites cater not only for the visually or physically impaired user, but they are in fact user, browser, device and search engine friendly. Not bad, eh?
Presenting information using web standards is good business sense.