Because change is hard, and most people have set their default search to google and won't take the action needed to change it. I changed to DDG a few weeks ago

Because change is hard, and most people have set their default search to google and won't take the action needed to change it. I changed to DDG a few weeks ago, and though it isn't as good as Google for geo-search and a few other things, but for the most part it suits my needs. But as YC always says, you need to be 10x better in order to get people to switch, and privacy isn't a big enough pain point at the moment for the general population to switch. It may happen in the future, remember, we made the switch from AltaVista to Google because Google search results were so much better. It is VERY difficult to get better at search than google, but that is what it's going to take, or a VERY painful reason for people to switch.