You are fed, clothed, and housed by the state. You have no luxurious amenities, no exercise of personal wealth, no contact with anyone other than for official business.
If you honorably discharge your duties to the completion of your term of office, you will be compensated for life to such a degree that you will never have to work again.
There's a lot of nuance that I'm glossing over, but the gist is that holding powerful positions ought to require severe personal sacrifice, but you will be handsomely rewarded after-the-fact if you bear that burden with dignity.