The primary drawback of the classic design of the cloverleaf is that vehicles merge onto the highway at the end of a loop immediately before other vehicles leave to go around another loop, creating conflict known as weaving. Weaving limits the number of lanes of turning traffic. Most road authorities have since been implementing new interchange designs with less-curved exit ramps that do not result in weaving. These interchanges include the diamond, parclo and single-point urban interchanges (SPUI) when connecting to an arterial road in non free-flowing traffic on the crossroad and the stack or clover and stack hybrids when connecting to another freeway or to a busy arterial in free-flowing traffic where signals are still not desired.