Kaiser is the first to admit that he was no soccer player. Instead, he was a man of connections. He befriended soccer players and told them to vouch for him, eventually getting a contract with a soccer club. He was in good shape and seemed confident, and there was no technology in the '70s to prove he was lying about his experience, so they just believed him.
Whenever it was time to actually play, however, he would "injure" himself, and when people started to catch on to his lies, he would move on to the next club. He also befriended higher-ups in the clubs and journalists that would write fake stories about him. He managed to become rich and famous while never scoring a single goal. Although what he did was wrong, you can't help but admire his dedication.