Without argument, one of the most important things to consider when creating a website is that it be accessible to everyone who wants to view it. Does your website play nice with screen readers? Can a user override your style sheet with a more accessible one and still see everything your website has to offer? Would another Web developer be embarrassed if they saw your code? If your website is standards-compliant, you could more confidently answer these questions.

via 10 Ways To Make Your Site Accessible Using Web Standards | How-To | Smashing Magazine.