A propeller blade or a compressor blade is hitting the oncoming airflow at an angle of attack that is determined by a combination of the rotational speed and the incoming airflow. When the incoming speed is low the angle of attack will be high. When the angle of attack gets too high the blade stalls, just like a small wing. So when the axial flow in a compressor backs up the blades stall and the whole thing turns to worms. Note that you can relieve this by dumping some late stage air to atmosphere - hence bleed valves.