It surprises me that there people still using WhatsApp given its bad security, and having to pay for it after a year? What keeps people from switching to other

It surprises me that there people still using WhatsApp given its bad security, and having to pay for it after a year? What keeps people from switching to other alternatives? Doesn't Telegram/Textsecure etc. offer the same, while being completely free? But I guess Facebook acquiring them explains it: I don't use Facebook either, so now I'm even less inclined to use WhatsApp.