How do we know the Drake equation wasn't created by some Alien inspired mathematician to cloak the fact that there are thousands of them living in the galaxy, and we are so insignificant at the moment that they feel the need to hide from us? Hmm my reasoning doesn't work!
No. Also, it was created by Dr Frank Drake
Anyway, who says the Drake equation is accurate anyway? I understand some statistics, but it's entirely possible that the equation itself is not accurate, but I guess it's the best that can be done with our current level of knowledge.
It isn't meant to be accurate per se, it's more of a starting point for discussion. Drake knocked it up a couple of days before a radio astronomy conference on ET life, because he needed an agenda for the meeting.
You can end up with billions of intelligent life forms, or 0.00000026 - depending on what parameters you substitute. It's all about best guess.