If you have a task with a %direction% reference, and the direction entered is "Up", then any attempt to store it in a text variable with the action:
Set TextVarX = %direction%
does not work (the contents of the variable does not change).
But any other direction does work.
If we try to use it in an IF expression:
<# IF( %direction% = "South", "yes", "no" ) #>
then the expression gives no output for direction "Up", even though it correctly responds "yes" for south and "no" for the other directions.