I can't listen to music when I ride my motorbike to work as I need to concentrate on the road. And if I was going to listen to a book at home I would need to make sure I gave it my undivided attention, otherwise I would miss parts of what they're saying.
Reminds me of the time when I tried to listen to a 'Japanese Language Class' podcast while commuting via car.
The first two lessons were OK, but starting with lesson three I had to decide between 'learn Japanese' and 'arrive at work in one piece'