Modern liberalism is not a political ideology. It’s a religion and a cult.
Liberalism is a religion of self-worship, which appeals to one’s ego of being capable of creating a utopia and of deserving to set your own moral standards (and NOT be accountable to God or others), and thus is very hard to give up. It is a reiteration of the original sin of pride. On the other hand, conservatism requires a humility to acknowledge that we are limited in resources, wisdom and character. That is quite a humbling step down for a Liberal to take.