The Why Christmas website explains that it was once a British Christmas tradition to place trinkets inside someone's holiday pudding. The nature of the trinket determined whether the person would receive good luck or bad luck in the coming year. If a single man found a button in his pudding, he would remain single for another year.
There were both male and female versions of the Christmas pudding tradition that dictated one's marital fate, according to the Why Christmas website. While men were given bachelor's buttons, women who were destined to remain single for another year were given what was known as the spinster's thimble. On the other hand, the website explains that a ring in your pudding meant you were either to be married within the year or to become very rich.
Sometimes six-pence golden coins were used instead of rings to indicate health, wealth, happiness or that the receivers would have all their wishes granted in the new year, a stark contrast to the ominous thimbles and buttons. Class Brain, an educational resource, insists that men who found a bachelor's button were actually destined to remain bachelors forever rather than a year, and that this is likely the reason why the depressing tradition eventually died out.