Puzzle of the Day

One well-known institution has a world-writable ftp subdirectory to allow outsiders to deposit items there for internal users, who may retrieve the items. The directory is periodically cleaned using a cron job which changes the current working directory to that directory and executes rm -rf *.

1. What are some problems with allowing outsiders to drop files off in an ftp area?
2. Does the solution adopted (to use the rm command to clean out the directory) overcome these problems?