That a von Kármán vortex street, as an asymmetric flow, can be generated under completely symmetric flow conditions is indeed surprising. Von Kármán proved theoretically that, in reality, this alternating vortex structure is the stable result. No matter what the initial state of the flow field is, it will eventually develop into this form. If the fluid is allowed to start moving from rest, which is equivalent to increasing the Reynolds number from zero, one can observe the entire process of the formation of a von Kármán vortex street.