Essence of the Phenomenon: During ascent, a rocket simultaneously accelerates and pushes through increasingly rarefied layers of the atmosphere. The point where aerodynamic stress on the vehicle's airframe peaks is known as Max Q.
Scientific Basis: Aerodynamic pressure is a function of air density and the square of the velocity. It is precisely at Max Q that the rocket endures the most brutal mechanical loading of the entire flight. Consequently, the flight computer deliberately throttles down the main engines to avoid exceeding structural limits.
Current Limitations: The slightest structural overload, a minor angle-of-attack deviation, or a hidden manufacturing defect at this exact moment can lead to the catastrophic disintegration of the launch vehicle.