Once upon a time a small company in Iceland made a sandbox game unlike any other.
The idea was pretty cool. 5000 solar systems, divided into 3 areas. One was supposed to be quite safe, one relatively dangerous and one completely lawless and deadly.
It was an awesome game. For a time - so where did it fall down?
I could write a one hundred page post on the aweful changes that were made but I'll focus on just one aspect for now and you can add some others.
CCP Fail Part One: Not sticking to the plan
When you write software you start with your plan. If the plan is not followed your software will be flawed.
When EvE launched the largest entity envisaged was the corporation. The idea of alliances were not part of the plan. The knee jerk reaction of adding alliances when corporation limits were reached was an ultimately fatal flaw.
The creation of alliances led CCP into a game damaging trap where players would add more stress on servers and CCP would play catch up to enable the servers to cope allowing players to add more stress ad nauseam.
An additional and more dangerous consequence of adding alliance functionality was of course that larger more powerful alliances preyed upon and drove off smaller corporations. Over the years the alliances grew to become a substantial real life power over the developers. When you allow ingame organiztions to grow to 10% or more of your playerbase (CFC at around 40,000 players) a significant change that negatively affects that organization can result in real life consequences to CCP.
CCP can now be held to ransom by a group of players as in the so called Summer of Rage.
Another consequence of powerful groups of players disproportionate to the average is that you end up with one type of player. If your 40,000 man coalition dominates every aspect of the game and drives away players of different play styles then you end up with a single type of player and if that type of player is not the average gamer then you limit yourself (niche).
There's a rumour that EvE was supposed to be a niche game however it was not. It became niche because of the deviation from the original plan.
When EvE released it contained and encouraged industry (mining, building, hauling, missioning), piracy (low sec, null sec), anti-piracy (low sec, null sec), empire building (null sec).
Today all but piracy and industrialism exists or in EvE terms PvP and Carebear. It's this way because by adding alliances one group dominated EvE, the PvPr, in domination it forced the other players of other play styles to choose alternative games, over time new players joined and those of the same PvP mentality stayed while those others quit.
This concentration of PvP mentality has led to a player community which is abusive, cynical and unwrlcoming to new players unless they express a desire to play the kill at any cost meta gaming mentality of the existing playerbase. It's led to the lauding of those who express the most antisocial hateful and abusive behaviour towards players who prefer industry or non-PvP activities.
It's a cancer that is hard to fix when fixing it can lead to a large proportion of the playerbase punishing you for change.