@Wisp @Hermes Let me give a quick hip pocket class on how percentages work.
If you advertise a 5% chance that something is going to advance (the mystery box) and I have 150 attempts, then on AVERAGE, I should have succeeded 7.5 times.
If I had a deck of 20 cards which contains one ace of spades then the chance that I draw that ace of spades with my first draw is 5% (1/20). If I keep drawing cards without putting any back then I can be certain after I’ve drawn 20 cards that I now have the ace of spades. (which is how Japan's L2 servers do events, which is fair)
(How YOU advertise that you do events) If I keep randomly drawing cards and put them back in each time, then each time I draw there is a 5% chance that I will draw the ace of spades. However there is no number of cards I can draw to be completely certain of drawing the ace of spades. In theory I could keep drawing forever without drawing the ace of spades though the chances that this will happen tends to zero as the number of draws increases. For example the probability after 20 draws that I have not drawn the ace of spades is 0.95^20 = 0.36. That means, out of 20 attempts, to NOT succeed is a 0.36% chance.
If we extend this out beyond 20 to say 100, there is only a %0.9941 chance of failure EACH TIME after 100. This means that every time I attempted to compound the mystery box after 100, there was a 99.1% chance that I should have succeeded based on pure random, eyes closed attempt, because I had not succeeded yet.
The Events that are given to players advertise a specific chance and we pay you REAL MONEY to take that advertised chance. You as a business are obligated to uphold that advertised chance.
I attempted to compound a level 6 Mystery box 150 times without a success, with an advertised rate of 5%. This means, according to REAL percentages, statistics and chance (not made up L2 math), I failed a 99% chance of success 50 times in a row.
Fulfill your obligations as a business and deliver what YOU advertise.