The most common reason why your beef ended up tough and dry in your Instant Pot beef stew is because the wrong cut of beef was used. Make sure to use a cut of beef that has a good amount of fat, like chuck roast. Also, note that not all cuts of chuck roast is the same. For example, prime grade chuck roast will have more fat than choice grade. You can already guess that the prime grade chuck roast will be very tender but still stay juicy and flavorful.