One thing developers of MMOs (and other games) have to decide is how much of their game they want to take out of the players’ hands and leave to “chance”. To determine who gets to be the lucky ones, they utilize what is often called a Random Number Generator (RNG). These can function in different ways, but invariably it comes down to the fact that random numbers determine if you were lucky enough to receive a certain item. In this sense it’s almost like playing the lottery.
The developers set the drop rate of items depending on how many they would like to circulate in the world. This is very important, because it determines the value and prestige of these items. Most MMOs have significant aspects that flourish entirely because humans are very reward driven. The chemical processes in the brain allow some people to reach the point of addiction when playing these games, and this is largely due to a chemical called Dopamine.
Continuous rewards for work (the carrot-on-a-stick approach) is therefore a relatively simple way to keep a game afloat. There should always be something to work towards or players lose interest. The number of players who stay to play these games entirely for gameplay (or other) reasons is too small to sustain development in most cases.
Random experience is a common way to ensure that certain tasks will, on average, take a certain amount of attempts (and therefore time). Other time-based restrictions are in rewards like the Laurels, which can only be obtained at a maximum rate of 1 per day and 10 per monthly achievement. This ensures that developers can price items so they know exactly the minimum amount of time it can be acquired in. Other MMOs employ similar tactics to create continuous rewards for work.
Human Flaws
This game utilizes the RNG for many things, including things like the frequency at which you obtain globs of ectoplasm from salvaging items. If a salvaged item has a 75% chance to give you a glob of ectoplasm, many people assume this means that every time they salvage 10 items, they will sit on 7 – 8 globs. This isn’t necessarily true. Just because a flipped coin has a 50% chance of “tails”, you are not guaranteed to get tails when you flip the coin twice. You could have a run of 5 heads, or 10. Even after you flip the coin after getting “heads” 5 times, you still have a 50% chance of getting heads again rather than tails.
Similarly, when you salvage items, you may not have 75 globs of ectoplasm after salvaging 100 items. Some will have less, some will have more. The problem is that you as an individual represent a very, very small sample rate, but because of the way humans function, you also value individual experience very highly. This means that if you receive less, you may be convinced that the chance is indeed not 75%. Something must be wrong!
Some of the people who experience this will then go to a forum, such as this one, and encounter another flaw in human beings: confirmation bias. If you see someone who agrees with you, chances are that you will latch on to this person’s opinion and value it over people who disagree with you, regardless of the evidence. The problem is augmented because people also have a tendency to voice complaints more than satisfaction. This means that people who have been less “lucky” are more likely to come to the forum and tell everyone about it. In this particular case, it may even seem like a lot, because the game has millions of players.
The developers, however, have access to all the data from all the players. When you look at a huge sample rate, the statistics will much more accurately reflect the specific drop rate. This phenomenon is called the Law of Large Numbers (in case you want to look it up).
Remember the saying: “Luck is probability taken personally”.