I personally like to support but refuse to do it because over 50% of the time my carry is either horrible or can't do the basic AD carry things like position, CS and have awareness. Since this is the case I try to only support when I have played with the AD before.

Normally I got to fight over solo top, not to be the "hero" but mainly since Nasus is very fun and really is the only carry I knew how to play. Most of the time am support or tank. Though, sometimes I end up being a carry support(Mostly as taric/nunu) Really it just seems to be a free-for-all over carries in general.