Let me help you out here with an analogy.
If you have 4 doors in your house, leaving them all open is insecure. Closing one of those doors has made your house 25% more secure. There may be other ways to get in, but one of them is closed.
Being 25% more secure allows you to focus that energy on guarding the other 3 doors, until such times as you are able to secure them.
Not closing the door that you CAN close is an invitation for everyone to come into your house.
