There were some famous accidents where rockets launched and just went up into flames. Many had something to do with leaking fuel in some sort.
I want to focus on aerodynamic stress however, like when a rocket deviates from its path or has a wrong angle of attack, what causes it to be destroyed? Purely drag force?
As an example: What mechanics were at work when an Ariane 5 was destroyed on June 4, 1996 due to an integer overflow? It just burst into flames!
Edit: Well, it seems like I may have been a little inaccurate. As many of you pointed out, fuel leaks are only a consequence of catastrophic failure. Additionally, most rockets explode only because they were told to do so to prevent damage to the vicinities.
What I actually meant was not what causes the explosion but why does the rocket break apart when not following the planned trajectory.
I thought it was because of the immense drag force when flying perpendicular to the velocity vector with high speed. In any case, thank you for your answers and comments, they gave me a much deeper insight in rocketry accidents.