What did nobles fear most?

Nobles most feared the loss of their power and privilege, particularly through rebellion or uprisings from the lower classes or rival factions. They were also apprehensive about the centralization of authority by monarchs, which threatened their autonomy and influence. Additionally, the spread of new ideas, such as democracy and egalitarianism, posed a risk to their long-standing social hierarchy. This fear often led to efforts to maintain control and suppress dissent.