The death of... ? (spoilers!)

I'm assuming this is in the context of the production with characters surviving and not the motive within the plot. In which case, it is all arbitrary... I mean, who "needs" to die? Though if you want meaning for it, think of like this... It was simply the only part of the plan that actually worked. If a killer fails every step of the way they just come across as a bumbling idiot who would be more suited to an episode of Scooby Doo, and not really an antagonist to be taken seriously in a movie intended to be an adult targeted thriller. It legitimized him at least somewhat as a viable threat, and furthers the importance of his defeat in the end.

Well, I didn't enjoy that part.

The sole purpose for his death was to make us think the other people had lost any chance to survive. And somehow it didn't work. His accident didn't sum up any tension to the movie.

But. He was driving slowly, was accompanied by a policeman and another policeman in the car behind. He just went out of the road and probably hit a tree. I think we are left to think he could have survived.