Times change, attitudes change, and people themselves change. Electorates have gradually become a higher proportion of the population, and it wasn't just a case of adding women: there were also limitations on voting rights for men, which have since been relaxed. At some time in the future, someone may be commenting that xxx was the first country to give children the vote and therefore the first-ever real democracy. Currently we don't even think of giving children the vote. But there must be at least some children who are more intelligent and better informed than some adults. Mind you, I suppose a line probably has to be drawn somewhere. It's hard to imagine babies voting, unless something transformational happens to babies.