Two National Geographic explorers explained that the driver should have started the car and left as soon as the big cat came close. This would have been the safest procedure for the tourists’ sake — no one could say what would have happened if the animal had been startled by the shoe-owner’s reaction; leopards, like all wild animals, can be extremely dangerous when they act out of fear — as well as for the big cat’s. If a leopard gets habituated to human contact, it may lead to human vs. leopard conflicts that will often result in the animal being shot down.
By remaining calm, the passenger avoided the worst, but the leopard’s claw drew some blood on their leg. If a simple pawing drew some blood and hurt so much, there’s no saying what a full-on attack could do.
Be sure to always follow all safety rules when embarking on an African safari. It could very well save your life and those of the beautiful animals you came to admire. 
H/T: National Geographic