I don't view the world through the lens of somebody else's pre-formed ideology, myself, and so when folks indulge in politics as if it involved the application of mutually exclusive dichotomies, I usually find myself objecting to the characterizations any "side" applies to the other. It may be comforting to view the world with rigid demarkations, but I think the world is more complex than that.
I see distinctions between liberals and authoriratian leftists, myself, just as I see distinctions between conservatives and rigid fundamentalists. IMO, one should form a view of the world from the bottom up rather than the top down by forming one's values first and then developing an ideology from the values rather than adopting the ideology and then twisting the values to conform witht he idology.
In terms of why one would be a liberal, though, I think it may help to discuss what liberality *is* rather than specific attitudes or policies to which somebody has applied the term "liberal" . In my own way of looking at it, one basic distinction between conservatism and liberality lies in the way one views social institutions, social order and traditions, conservatives placing a higher value on the preservation of institutions and order (the "conserve" in conservative having to do with conserving institutions) and liberals a higher value on social justice and an increased willingness to change these institutions. Women would not be voting were it not for liberal ideology.
There are certainly extremes involved no matter what the ideology, and imo, most of the extremes derive from people who do not understand the underlying values and who either simply conform to the label or react againstt he opposing label. Conservatism taken to its extreme can result in societies in stasis as institutionalized oppression (political Islamism being a prime example) whereas liberality taken to its extreme can end up with an approach that throws outt he baby with the bath water, failing to preserve that which *should* be preserved.
In any case, I would say that the best approach to politics is to base ones attitudes on real values rather than deciding one is going to be a "conservative", a "liberal", a "libertarian" or anything else.