Trains must follow the track. As long as they stay on the track and the track is set to the correct destination the train will arrive at the designated spot. That is unless something goes wrong at the switch point. If the switch point is off the train could end up thousands of miles off course with no way but to go all the way back and try it again.
Trains and their switch points are similar to us and our earth life. We have an Eternal destination we are trying to get to and there are many switch points along the way that will either keep us on track, or turn us thousands of miles off course. This lesson was about 4 switch points in our life that are especially important to pay attention to.
The side note:
These are great questions to post while people are coming in the room, gets their brains thinking and ready for the discussion.