how does the boat of the three friends became a source of trouble for them?

The men aren't great at docking the boat. They have a hard time finding places to pull ashore, discover a woman floating in the water (a suicide), a dog in the same condition (poisoned by river water), cannot wash their clothes from the boat (they're left dirtier than when they began), they fall overboard, pass their destinations, and are generally miserable...... which leads them to abandon the trip.