AI models often exhibit biases in their responses due to their training data and the way they generate random numbers. It's likely that '17' is a number that appeared frequently in the training data or is a number that the model, for whatever reason, favors. Additionally, AI models can sometimes mimic human biases in number selection, tending to avoid very low or very high numbers. Therefore, it's not truly random, but reflects a combination of biases and learned patterns.