The OpenStack Architecture Guide states in the section about the general purpose architecture:
"For cloud domains that require increased computer security, network security, or information security, general purpose cloud is not considered an appropriate choice."
It doesn't explain why, and what this architecture's shortcomings are. I also didn't find any hint in the other compute- storage- or network focussed sections, why these would be superior. Their security aspects are just described in more detail.
Could anyone elaborate on the inappropriateness of the general purpose architecture, and what to watch out for?