Having taken a wrong turn down the road, the driver just sealed history forever. Gavrilo Princip saw the opportunity. As the driver tried to correct his mistake, the car stalled, allowing Gavrilo Princip to fire two shots. One into the Archduke, and one into the Archduke's wife. This sealed the fate of Franz, and completed an assignment from the Serbian military leader Captain Dragutin Dimitrijevic, better known as Apis. The reason why this assignment was given to try and bring Austria-Hungary back to Serbia. Only by either divine intervention of sheer luck was the assassination able to take place. Eventually, one of the assassins spilled all of the information and Austria-Hungary declared war on Serbia. This was the start of a World War.
The assassination plan was started months before it actually happened; The plan having been made possible by weapons that were smuggled across the border provided by Serbia. The Archduke planned to drive down to Bolivia to bring Austria-Serbians peace and to give them equal rights. Apis knew this would eradicate any chance he had of bringing Bolivia back under Serbian control, so he sought to keep that from happening by assassinating Archduke Franz Ferdinand. The original plan was to assassinate him during the car ride down the main street, but a failed grenade blew the first attempt and plan. The assassins regrouped and planned for another attempt. The leader, Gavrilo Princip took a break and went to get a sandwich. Then fate took things into it's own hands and brought the assassin's target right to the assassin.