Elizabeth Dwoskin, writing for The Washington Post:
The WhatsApp co-founders were also big believers in privacy. They took pains to collect as little data as possible from their users, requiring only phone numbers and putting them at odds with data-hungry Facebook. At the time of the acquisition, Koum and Acton said Facebook had assured them that WhatsApp could remain an independent service and would not share its data with Facebook […]
Another point of disagreement was over WhatsApp’s encryption. In 2016, WhatsApp added end-to-end encryption, a security feature that scrambles people’s messages so that outsiders, including WhatsApp’s owners, can’t read them. Facebook executives wanted to make it easier for businesses to use its tools, and WhatsApp executives believed that doing so would require some weakening of its encryption.
Facebook’s Mark Zuckerberg and Sheryl Sandberg don’t know when to stop.