Could it be just randomness? You can pick either way, and somehow one particular direction became more popular, and get over the "tipping point"? It's the same

Could it be just randomness? You can pick either way, and somehow one particular direction became more popular, and get over the "tipping point"? It's the same with traffic rule, right? We could either go on the left side, or the right side of the roads. We happened to pick the right side, and everyone is driving on the right side now. Oh wait, the poor Brits are driving on the left side, and traffic must be chaotic over there :)