The Big Wand is able to generate the magic by converting human belief in fairies into power. Until recently Mr. Crocker was the sole source of the wand's power due to his constant belief in fairies and almost always spasming about them, but after he temporarily stopped believing in fairies thanks to Dr. Fancyfree hypnotizing him, the Big Wand was drained of all of its power, and Fairy World became a slum. After they were able to convince Crocker fairies existed again, they also began to draw power from Crocker-like people from all around the Earth so that this black-out would not happen again.
In The Jimmy Timmy Power Hour, Jimmy tries to fix it after Crocker knocks it down, but despite his best attempts, it still wasn't working. He then found out the Wand was unplugged and he plugs it back in to get it working again.
In Channel Chasers,Mr.Crocker lost his belief in fairies due to The Magic Remotes,therefore shutting down the very power source of all Fairy-Related Objects and creating a time paradox that could destroy the universe in real life.