In my humble opinion, it is "balance". This simple, seven-letters-long word encompasses many variables, all of which must be taken under consideration. It is a mix of what the player is given, or the "tools" one has at hand to complete each task, how demanding said task can be and how much "fault" is allowed to the player.
Most people make the crucial mistake of branding a game "cheap" when the third of these characteristics is in effect. If a task requires great precision it is likely that most people will just give up, call it unfair and be done with it. But is a title's lack of fault-tolerance really reason to consider it "unfrair"?
No. Games, at least those aimed at the "hardcore" pool of gamers, are supposed to be challenging. You cannot expect to find challenge when a game forgives your going to the kitchen to prepare a sandwich while it is running without consequence or effect. If one has to step on a certain milestone then that step has to be earnt. It's the subtle procedure - or exchange if you prefer - of "challenge" and "reward" that is the driving force behind gaming, and, behind most of the actions during our lives.
Of course, like most things, fault-tolerance can be miscalculated, botched, abused. In this case we are looking at the very common state of "cheapness". When a game gives you too little and demands too much putting just a little less of the above quality in it can have disastrous effects. Automatically, it falls from the graceful, respected position of "Difficult" into the void of "Cheap"... in other words, it becomes imbalanced or, as the "technical" term stands in the ranks of gamers everywhere, "imba".
"Demon's Souls has to be the fairest of all extremely-demanding games released in the past five years. It bears a close-to-zero tolerance for mistakes but offers great precision to the player. That, along with the abudance of choice in character builds and equipment makes it absolutely possible to survive any situation. Fine print is that, if you are not careful or prepared, any and all bad decisions will lead only to one outcome: Death. You will be dying a lot in DS. The Knight on the cover, peppered with arrows, is a testament to how demanding From Software' s masterpiece is. Make no mistake however: You CAN prevail against those odds... if you are dedicated enough in your efforts..."
Understandably, it is impossible to be exact in such statements if specific titles don't get named. In this part of my article I tried to pass along some of my thoughts on what makes a game imbalanced and infuriating. In the second, upcoming entry, I will analyze specific cases of games - along with their sequels - regarding the lack of balancing and, in certain cases, the decrease in said quality from one part of a series to another.
Until then, best regards and I hope you found this read interesting.