am running a cron job to do a backup of all user files. the script runs properly in the terminal but only backups about 20% of the files when run by cron.

the Linux system is running BASH as far as I can tell.

the symbols $FILE and $DIRECTORY are defined properly and the following is the active line which causes the backup to occur:

NAME=userName;
#
DIRECTORY=~/$NAME;
FILE=$DIRECTORY/`date '+%y%m%d%H%M%S'`_$NAME.tar;
#
tar -cvf $FILE $DIRECTORY/html;

what do I need to do to get cron to create a tarball of all the files?