A couple days ago, I was looking at an algorithm FAQ for Final Fantasy VI on GameFAQs. Looking at the game's actual damage and hit formulas really reminded me who opaque the game's mechanics are to the player. In many ways, Final Fantasy VI can be very frustrating to play thanks to this lack of transparency, since unless the player does some in-depth research, it can be nearly impossible for the player to accurately predict the outcomes of his decisions.
Let's look at three Relics that can be equipped on a character in order to increase that character's physical attack power: the Hyper Wrist, the Atlas Armlet, and the Gauntlet. The Hyper Wrist boosts a character's Vigor stat, which is one of the attributes that determines attack power. The Atlas Armlet's description says that equipping it will boost the character's Fight damage. And finally, the Gauntlet doubles the Battle Power of the character's equipped weapon by wielding it with both hands. What is not clear at all is how effective these various Relics are in comparison to each other. While the Gauntlet sounds like it should double the damage output of the character equipped with it, the actual increase in damage is significantly less than that. So appraising which of these Relics is the right one to equip on a character is really difficult.
Another area where trouble arises is in determining which stats a character should raise. There are four main stats: Vigor, Speed, Stamina, and Magic Power. However, the game itself is tight-lipped on what each one does. Of these, the only one whose name is self-explanatory is Magic Power (Speed is a distant second). However, since the player can only guess at what each stat does, it is impossible to build stats up intelligently. The player can really only stumble around in the dark. Apparently, based on the FAQs I have read, the stats are not even all equally important. Stamina in particular gives only minor benefits, despite being listed alongside Vigor and Magic Power, which are really important stats. So the lack of info creates major traps that an unassuming player can walk right into.
Another major problem is that the game doesn't really tell the player which stats will affect which abilities or attacks. For example, I am still unsure which stats are important to Sabin's Blitz attacks, even after reading a detailed FAQ. It is unclear whether equipping him with better weapons will improve his damage, whether or not Vigor or Magic Power are used to calculate his Blitz's attack power, or even if it varies based on the individual Blitz. Since Sabin is obviously a big fighter type, and he has naturally high Vigor and low magic Power, it would make sense that Vigor is the pertinent stat and that Magic Power can be safely ignored. However, that common sense conclusion might not be the correct one.
All told, the lack of transparency about the math that Final Fantasy VI is built upon can make it very easy for a player to unintentionally gimp a character, and then leave that player struggling to figure out what went wrong. An RPG needs to be straightforward and clear about what statistics do what, the exact effects of equipment, and which stats abilities are dependent on. It is only with that knowledge can a player make reasonably informed decisions.