Google reads your email, reads your chats. It knows what you’re searching for. It sees you when you’re sleeping and knows when you’re awake. And the server is economically incentivized to remember. The way to make money on the internet these days is to get people to exchange personal information for free, and you get them to do that by making them think they’re just interacting with the service: sending an email or searching or chatting with a friend. But there’s this underlying architecture there.
Google just updated their privacy policy to explicitly state that they read your emails and your chats to better serve you targeted advertising. The final straw for Google was when they changed the privacy policy in 2012, and that they aggregated information about you on all these platforms.