A general idea of where machine learning is applied is readily available. But in which case where even when a rich training set is provided, the problem can't be solved through a machine learning algorithm? Where they shouldn't be used and why?
The best example would be predicting stock prices as they depend only on the current demand and availability of stock. Even when abundant historical stock rates are available to the public, machine learning methods cannot be applied on them for future price prediction.
I would like to know more of such practical examples.