5 Important Things In The Harry Potter Universe That Quickly Stopped Mattering

5. Floo Powder

The Moment It Stopped Mattering: Just after it had served its purpose as a plot device. Look, I hate Floo Powder, and in the interest of full disclosure, I hated it from the first moment it was described to me. "Just grab a handful of this shiny cocaine and toss it into the fire. When the flames turn green you can go to ANY fireplace ANYWHERE." Footnote: You have to speak stupidly clearly. Harry pronounces it DIAgon Alley instead of DiaGON Alley, and winds up in... Knockturn Alley? Those words don't rhyme. They don't even have the same number of syllables. According to the Harry Potter Wiki, Floo Powder was invented in the 13 century: you'd have thought that in 700 YEARS some bright spark wizard might have worked out some of the kinks. But that's the thing, we needed that kink to get Harry to that other place so he could overhear some crucial information or whatever, completely by accident. After that one scene that Floo Powder was invented for, nobody really ever uses it, except to make phone calls, for which people actually stick their heads in the fireplace to talk to other fireplaces. After the Quidditch World Cup incident, Molly Weasley even feeds Amos Diggory a piece of toast while he's on a Floo call to her husband, which is pretty much the best and most exciting application of Floo Powder in the history of wizardry.