In a feudal system such as the late Han dynasty, appearence is everything. Liu Bei needed to look like he was indiferrent to power. This, allowed him to gain legitimacy, in a land where it represents everything.
Every great warlords of the time thought that way. Even Cao Cao, who was arguably the most ambitious, always needed to keep his appearences as the loyal protector of the Han emperor.
If they can abolish fanaticism, let us pray for the advent of the sceptics.
The Opium of the Intellectuals