For what purpose did Hannibal make the most difficult crossing of the Alps? What was he counting on?

Hannibal began his campaign from Spain, then lay in front of him a difficult campaign across the Alps. He hoped that in this way he would catch the Romans by surprise. True, the transition through the mountain system turned out to be much more difficult, in connection with which, Hannibal lost the war elephants, on which he had pinned great hopes. But despite this, he was still able to inflict a number of defeats on the Romans, the largest of which was the Battle of Cannes, which took place in 216 BC.