I always thought of it as a catchy phrase that I never thought too much about.
So, thinking about it (just off the cuff): To me it implies a precarious balance, on an edge that will hurt us if we fall but since it is on a crossroad the freedom is there to go in any direction we would like.
It doesn't really feel like something I can relate personally to, though.
Howzzat fer a pair of centavos, chica? Que?
helen