Why is the function of urination hidden by a strong social taboo in every culture on Earth?

Answer 1: The function of urination is hidden by a strong social taboo in every culture on earth since it contains the part which brings forth to life.

Answer 2: I also believe that it reminds people that we are mortal and going to die; and that it causes people to temporarily doubt the importance and meaning of all pomp and pretense that is a crucial part of what caused us to evolve upward as a race: CULTURE. Without Culture, the entire world would collapse: families would fall apart; religious institutions would turn to chaos; the financial system would collapse as social order crumbled; there would be rioting, looting, pillaging and arson, and much worse, in the streets all over the planet; martial law would take over; all Taboos would be lost; wars would erupt as never before and go nuclear immediately; Armageddon would arrive. Sic Transit Gloria 'Homo sapiens sapiens'!