There are requirements for commercial flights which would be extremely hard to achieve with a rocket architecture. For instance, you cannot have a single failu

There are requirements for commercial flights which would be extremely hard to achieve with a rocket architecture. For instance, you cannot have a single failure (whatever its probability) that leads to a catastrophic condition. Meaning, for every component and at every moment, you have to assume the component fails and still have to ensure you don't kill your passengers.