“Go With Your Gut And Trust Your Instincts” is a popular saying that fits right into many situations. Suppose if some of your friends jump off a building, will you do the same? Obviously not, because a common concept among humans indicates that having a door with no glass means its not safe to pass or walk through otherwise something bad is going to happen after passing the door. So, it is a must you wait and watch if the door is opened and passed by someone accurately. This is what my dog knows.