I saw this board outside my house, advertising a jackpot of € 21 million. Below, it has some more text in smaller font explaining how the win likelihood is 1 in 95 million. I’d wager that German regulation requires the lottery company to declare this.
While I always knew that the odds in a lottery were long (lottery companies have to make a living), I was surprised by how slim they were (instead, they were making a killing). In effect, if 9.5 million people deigned to purchase €10 lottery tickets, a mere handful would stand to win a total of €21 million.
When a massive €21 million jackpot is advertised, it is difficult for a person buying a ticket to grasp what that means. It helps, through regulation or otherwise, to include the denominator, declare the odds and put that number in perspective.