Missing the Forest for the Trees

Let's pretend for a moment that I was a professional illusionist. I have a trick I want to show you that involves my garage.

"Behold," I say, "inside my garage is a green Ferrari."

I open the door and my garage is sadly empty.

"Hmm. I must have messed up something - let me try again. Abracadabra - a red Ferrari."

On closer inspection there does appear to be stuff in my garage. Camping gear mostly, some junk, but definitely no vehicles.

"Green and red didn't work. I guess it must be blue. Alakazam, feast your eyes on my blue Ferrari."

My garage remains devoid of sports cars.

"A yellow MG?"

Nothing.

Now how long would this charade have to continue before you concluded that the problem wasn't the colour it was that the trick didn't work at all? And also that I was a piss-poor illusionist.

In unrelated news, the end of the world has been rescheduled for October 21st.