"The problem is that people across the world, most of them in the developing world, use old phones or desktops that don’t update themselves, and they won’t be able to access the internet,” Matthew Prince, CEO of CloudFlare, told Buzzfeed News. “For the developing world, on average, 4 to 5% of visitors will simply be cut off.”
While that sounds like a minor percentage, it extrapolates out to about 37 million people worldwide, with the hardest-hit regions including China, the Middle East, and parts of East Africa -- more than 6% of people in China, in fact.
If you're not a tech wonk, the simplest explanation why is this: the current technology that creates that https (as opposed to http) and the green lock that signals a secure connection on your browser has been deemed outdated and unsafe from cyber attacks. The web is shifting toward an updated version of secure encryption to make your browsing more secure. But sites like CloudFlare and Facebook have suggested the deadline of January 1 for the new encryption is hasty and will discard millions of people who don't have a choice in their Internet-enabled devices.