Think it's a minor mistake? Think again. The shamrock has deep roots in Irish history. According to Irish Central, "St. Patrick arrived in Ireland in 431 and converted the Pagans living on the island to Catholicism by using the shamrock to represent the Holy Trinity ." Shamrocks have three leaves, which represent each part of the Holy Trinity. And like that religious belief, the three parts are separate, but also one entity, just like the shamrock's leaves connect to one stem. While those unfamiliar with Irish tradition or Catholicism might overlook the mistake, but for those in the know, it's pretty glaring.