Columbus wasn't looking for America. He had miscalculated the circumference of the earth and thought he could sail west to India. The Portuguese laughed him out of the country because of this. Note that the Caribbean was called the West Indes for this reason -- Columbus thought he had hit India.
Sure. But the bet on finding something paid off when others would not have made the journey. The outcome was something nobody expected. They were both wrong.
For someone to be wrong, they have to have made a some statement that turned out to be incorrect. The people that disagreed with Columbus' calculations said that the earth was larger than Columbus gave it credit for. This was not an incorrect statement.
