You need to explain why obviously broken systems persist, or why your own drastic move is the reluctant last resort rather than the first impulse.

This is the document's conservative valve, and it is there to make the revolution credible. By admitting that people endure far too much for far too long, the authors inoculate themselves against the charge of hotheadedness: if even these patient sufferers are rising, the cause must be grave. It is also a cold piece of political psychology that still holds — the status quo has a gravity of its own, and "the forms to which they are accustomed" will be defended by the very people they crush. Anyone trying to move a system should expect this drag and plan for it, not be surprised by it.