Liberals used to be called progressives, why did they change their name to liberal?

If the basis of the word is liberty, I am unclear when and why progressives changed their moniker. It strikes me that conservatives are more rooted in personal liberty than societal fairness (one of the basic tenants of liberalism), and that personal liberty is more in line with the term liberal. Thus, it seems like conservatives should be called liberals, and liberals should be called progressives.