It is easy to explain if the names all start with a different letter.
Sort Anna and then Anne becomes harder. The ">" sign or the "<" sign (depending on your sort algorithm) compare each letter in turn until the inequality triggers, which it will do with the last letter in this case. Young childers can understand that.
Then try explain the order 1, 10, 11, 12, 2, 3, ... 8, 9 if trying to sort numeric strings 1 - 12 in BBC BASIC without going into ASCII
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