I just plain don't understand these security questions!! Am I an idiot!?! They can't possibly increase security. I was quite upset when Apple forced me to add

I just plain don't understand these security questions!! Am I an idiot!?! They can't possibly increase security. I was quite upset when Apple forced me to add these to my apple ID. Of course, I treat these questions like additional passwords. I write down the question in my password keeper, and input a random phrase into each.