In the modern world, most car designs were specifically invented to traverse asphalt and or all kind of terrains.
However, their shapes remained the same despite the variety of their size, length, and width.
Lori: [Yeah. We'll need an hour to replace that generic-looking square body of the wagon.]
Jai: [Eh? But isn't this already good enough?]
Lori: [Aha... That doesn't work like that. The design is too big, flat, heavy, and air resistant. Plus the square shape brings the center of mass higher than the ground. I explained it earlier, didn't I?]
Lori only proudly placed her hands on her waist but looked at Jai who was still clueless and said "Huh?" after all that made her think that it was a waste of time.
Lori: [Anyways. You can stall your trip for an hour and come back later. You won't need to bring two more wagons to carry the gifts you have!]