Three Winning Predictions

A man had been receiving emails predicting which horse would win a race. The predictions were right three times in a row, and he was about to pay a large fee for the next one. But when he learned that emails from the same sender had stopped arriving for a friend partway through, he decided not to pay. What did the man suspect?A man had been receiving emails predicting which horse would win a race. The predictions were right three times in a row, and he was about to pay a large fee for the next one. But when he learned that emails from the same sender had stopped arriving for a friend partway through, he decided not to pay. What did the man suspect?