Because that's bogus. ... when the loot is purely RANDOM, time invested still means nothing. Random is still random, and in random loot systems, you will have people who will always fall to the extreme ends, either not get anything, or getting too much. Time invested doesn't apply, unless there are modifiers (I doubt it) that increase your chances over time, then again, random is still random. Time means you will get more attempts, but it doesn't mean that your chances will be any better. That's a problem when the idea is supposed to be "earn" your loot.