First, not all that presents itself as conservative is actually conservative.
The Republican Party poorly represents conservatism. In fact, the GOP vacillates between moderately conservative on some issues and liberal economics and internationalism. I would guess that a third of the GOP is actually liberal, a third sticks a wet finger in the air, and a minority is actually conservative. For example, George W. Bush got tax cuts passed early in his administration, but cooperated with Democrat-led bail-outs of banks and GM.
So, let's not use Republicans to define the opposite of liberalism.
Second, being liberal is a good thing; and progress is good when the goal is good and the means are just. Being a liberal or a progressive, however, has a very peculiar meaning that does not necessarily connect to the root words, liberal and progress.
In my definitions (not necessarily standard, but offered for the sake of communication), conservatism seeks to preserve traditional values of liberty, self-reliance, and justice that does not respect persons.
Liberalism, or as the codeword is used today, progressivism, on the other hand, redefines a neutral term. Progress is good, right? Doesn't everybody love progress?
When you say change (as in hope and change) or progress, you have to pick a direction. You have to pick an origination and a destination. Depending on your definition of progress, it may or may not mean something good. The compass has only one North, but it has 359 degree-markers that point away from North.
Suppose your objective were to see far with an unobstructed view, so you climb the highest mountain. Progress would be pretty stupid if it meant trekking off that cliff to the West, wouldn't it? What else could you do? You could build a tower where you are, on your existing foundation. But would you leave the spot just because change is good?
The progressive compass points hard left, to 270 degrees, toward freedom for immorality and toward repression of traditional morality, toward collectivist statism, and toward "social justice" that bases rights on class, skin color, and sexual orientation.
American conservatives see progressive, liberal, socialist, and Marxist, as variations of a single philosophy. That philosophy derives from secular, materialist existentialism, in which interpretation is reality, objective truth is a myth, and the ultimate organism is the state.
Whereas Americanism states that authority flows from God through the People to the government, the progressive spectrum worships the Collective as the ultimate organism, whose people live at its pleasure. Americanism secures rights to the people and assigns responsibilities to the government, but progressivism gives the government rights and the people privileges.
Conservative liberalism means personal tolerance and personal giving (to which the restaurant help will attest after any political convention), but Progressive liberalism forces promotion of the tolerable and gives at the expense of others.
If you believe black is white and right is wrong, then, I suppose, being a liberal is great.