Admins do get money hungry.
I'm a highrate player, personally I want to jump in the game towards PvP instead of spending most of my time leveling and hunting for things that don't want to drop. Some may say that I just want things easily, I agree that I do, but who wouldn't? A player should spend most of his/her time in game learning how to play better not figuring out what items they need to overcome another player.
Sometimes this can be the reason why servers go bad. The staff make it seem too item dependent; meaning having the right items serves a great portion of a battle than having the right skill. Too many servers make it "The longer you player, the better you are" instead of "The harder you play the better you will become". Obviously, the longer a player plays, the more time he/she has to obtain items on a low drop rate. Yet, that's just Lowrate, in which I see is a big waste of time for players.
With high rate anyone can get the item they need, fight me on the same level in a fraction of the time. They don't have to spend countless hours for a item to PvP with someone they cannot beat.
Like I said before, some server go bad because Admins get money hungry, they know players want to be stronger than everyone else. The fastest and easiest way for an Admin to provide this to a player is by giving him/her strong items noone have for a price. This is rinse and repeated a few more times until an admin finally decides he needs to make a new item, so that player can be stronger than everyone else again.
Some Admins stray from that idea and instead make servers more balanced, donation items and custom quest items have the same stats and ofcourse donation items are faster to obtain, but serve no real difference to custom quest items. However an Admin maybe too focused on this idea and make the quest nearly impossible or repetitive to complete. In which a player will soon see no motivation to complete the quest because it just simply takes to long and takes time away from the game.
Another reason could be; Server Rotation. The Staff team is so focused on putting quests and mobs in the way that they forget about rotation. Rotation is the idea of letting players take a break from countless hours of leveling and hunting and play some competitive gaming. Such as PvP or Mini games in which you win items on the side. A cat cant chase a mouse without the mouse, and players wont play without a prize. Staff find it very dangerous to give items to mini-games or PvP matches because it could be exploited. However, this can be avoided in many ways, such as Custom Consumables or Prize BoX where the player opens the box and has a chance on getting an uber item or a custom consumable. Noticing this, Staffs make the assumption that it is dangerous and refuse such a thing. And so on people will get bored in server doing nothing, sure they can finish quests and go hunting but that too is boring and repetitive. So if anything server rotation is a must, you need to keep the players mind stimulated with choices; Capture the Flag, 3v3, 5 Man free for All, and so on.
Having bad players is something every staff should ignore, if anything a player is a player. And you could release some aggression in PvP to release it. Having enemies/bad players give players the will to play and challenge them. Sure the Staff cant please everyone, but they certainly make them understand the issue. Even bad players advertise the server. If anything a bad player should be considered a player before everything. In my perspective a bad player is just someone who doesn't agree, much like saying someone that has their own opinions or the lack of intellect to understand something at a specific level.