I think it's because all the relevant dimensions are so vast: - devices: desktops/laptops, smart phones/dumbphones, lynx, curl, uncountable browsers - program

I think it's because all the relevant dimensions are so vast: - devices: desktops/laptops, smart phones/dumbphones, lynx, curl, uncountable browsers - programming languages / paradigms: in the end it's all HTML/CSS/JS, but there's lots of ways to generate these - in whatever PL you selected, a bewildering array of libraries - open source and commercial offerings - small single site pages to things like MSDN - public facing pages to large internal legacy intranets - use-cases, from wikipedia to youtube - running in a browser vs in a container like the spotify app - languages (like english vs german), so unicode etc. issues - vast amount of developers doing the work, with very different backgrounds To the degree things works, it's small wonder really :)