Would you feel good driving down a highway where all speed limits had been removed?
Works for the Germans
They just kinda recommend what they think works and let you decide whether you like it. I think it's called voluntary compliance.
That's not really true. On the autobahn there are parts where there actually is a limit, parts where its just suggested, and parts where there aren't. There are also rules to passing. Finally, it doesn't just "work out" for no cost, if you crash and you're going above the suggested speed you will be prosecuted, and in fact in some cases if YOU get hit, but you were the one speeding, the other driver can get the costs split between the two of you.
Be careful what you wish for. And for all that, they only really go like 85-90 on average there anyway.
As for this OP, if you meant actual liberalism from the 18th century or so, then I support it because it maximizes people's freedoms while balancing out the reality that despite their being a need for small government, there still is a need for it in crucial aspects and seeks to reach that balance through an equilibrium of personal freedoms, individual rights, and provision of equal opportunity, not material goods.
There is definitely some value in traditional conservatism too, but I prefer the liberals even to many libertarians in the sense that there are truly times where I know for a fact that people simply couldn't handle or desire that degree of freedom on a mass scale (like Ron Paul's dismantle the entire treasury. If you aren't going to replace it you must be ******* tripping to think Americans will suddenly start bartering or figure out how to make their own dollar bills).

