OOP: Common Room Passwords

[stardreams04]

No: HPFGUIDX 64715

<snip>
When I first heard that it was the password I thought maybe they 
chose that as the password so that this time Neville would actually 
stand a chance at remembering it.  :)

What I want to know is... In previous books, the password changes 
periodically. In PoA it changed every day, but even in the other 
books it changed every month or so. WHy did it stay the same all 
througout this book? I always thought the changing passwords were 
very whimsical and a cute touch.
<snip>

I liked this idea, too, since it seemed like something the 
Gryffindors would do. But who sets the passwords? The prefects? Of 
the Gryffindor prefects, only Hermione and Ron (5th years, and 
therefore at the bottom of the hierarchy) knew that Neville owned 
such a plant. Of course, they could have suggested it to the older 
prefects...(Who were they in Gryffindor, by the way? Do we ever find 
out?) In any case, it DOES seem weird that the Gryffindors never once 
changed their password - not very good for security. I guess they 
quickly forgot Moody's warning of CONSTANT VIGILANCE! 

~stardreams04