"Yes, to Mordor,"... "in that land he would learn much, too much for his comfort. And sooner or later as he lurked and pried on the borders he would be caught, and taken - for examination. That was the way of it, I fear. When he was found he had already been there long, and was on his way back. On some errand of mischief. But that does not matter much now. His worst mischief was done."
Gandalf goes on, and at this point in the story we do not know how late it is... This was such a scary part of the film, when we knew the black riders were already near.
Have fun!