The door may be unlocked but you still have to open it to get inside.

You can't go through your life with blinders on or you will get blindsided by reality. Even when you choose the straight and narrow path there will still be boulders that fall suddenly and block your path. You will then need to walk around it or you will hit it head on. As time goes by in our ever changing world you can't even rely on the things that use to work before. You have to keep your eyes wide open as you go throughout your life and be flexible enough to bend like a pretzel if it is necessary to keep yourself on track. Keep in mind that usually when one door closes another door opens. But if you don't keep your eyes wide open and look for a door that opens you won't see it. The door may be unlocked but you still have to open the door to get in.