Most safety features in your car are not meant to prevent an accident, but instead are there to make sure you survive through the accident. No matter how safe of a driver you are, there’s still a chance someone else is going to crash into you.
The Bible never says the life of a Christ follower is going to be free of tragedy. Scripture can give us wisdom in how to handle situations in ways that can avoid pain, but the fact of the matter is that we will all face suffering in our lives eventually. God doesn’t promise us we’ll get around them, but He will get us through them.