You're all confused. I will water it down:
When a hurricane, e.g. Katrina, cause a lot of widespread damage and distress, they choose to rename it once the letter (in this case, 'K') of the gender (female, in this case) recicrles and comes back. They don't name hurricanes by random names, they have a set list alphabetically, and every 52nd hurricane will have the same name, as, for example, A is male, then B will be female. However, they change the name because if, say, for example Katrina's second round came along, people would instictively consider it to be as bad as its namesake, and it would probably cause a lot more commotion that it is actually worth, as it could easily be a Category 1 hurricane or a tropical storm when it makes landfall, therefore reducing damage to a minimum. It is so that people will not panic when there need not be.
That's to the extent of my brilliant knowledge. There might be more on the matter, but I'm not sure. It's been quite some time, so my information may be rusty, even with my photographic memory.
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