“Cithrin?” he said. “Why won’t I lend money to the prince?”
“Because if he doesn’t want to pay you back, you can’t make him.”
Magister Imaniel shrugged at Cam. “You see? The girl knows. It’s bank policy never to lend to people who consider it beneath their dignity to repay.
Komme Medean's policy not to lend to nobles comes up again in The King's Blood. This was a real-world, historical phenomenon. Absolute monarchs were terrible debtors. Historian Niall Ferguson puts it this way in The Ascent of Money:
Investors in royal debt had to be wary. Whereas towns, with their oligarchical forms of rule and locally held debts, had incentives not to default, the same was not true of absolute rulers. As we saw in Chapter I, the Spanish crown became a serial defaulter in the late sixteenth and seventeenth centuries, wholly or partially suspending payments to creditors in 1557, 1560, 1575, 1596, 1607, 1627, 1647, 1652 and 1662.
The British monarchy, by contrast, accepted constitutional limits on its power. The King's power was balanced by Parliament, whose members owned at least some of its debt, and wouldn't let it default. The British Crown was then able to borrow money at much better rates.