A car carrier driver makes money from the cars that he transported into its destination. He needs assurance for delivering all those cars safety or he would get fired by his boss. If that happens then the company would get a bad reputation and might not get the same costumer again. It is always hard to get a new customer, but it is harder to keep an old customer. So, he would not give the driver a good review if the driver put it in his resume. The driver would have a hard time finding a job because of his reputation and that would be bad, both for him and his family. If the driver can't get a job then how can he feed his family. That is the reason; why a driver makes sure that the cargoes are safe in his truck.
In this game, you won't be just driving the truck, but also the car that would be at the back of the truck. The car owner would need to go to the bank to withdraw some money before he can get over to the car carrier trailer. You would need to repeat the process till all of the cars are properly placed at the back of the truck. Try not to damage the truck while driving. This game has a time limit, so try to make haste.