A while back Fortnite had a type of challenge known as Rare Quests. You could complete various stages and they would usually become progressively more difficult to complete but they'd give players a good deal of experience points to reward them for their hard work. Milestones work quite similarly to Rare Quests except they've been tweaked here and there, hence the new name for them.
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The difference is that with Milestones you always have to complete a task a
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