Condition is most of what a card is worth, and condition stays an argument until someone settles it. One collector's near mint is another's lightly played, and that gap is where deals fall apart.
A PCG grade settles it with four subgrades rather than one number. Centering, corners, edges and surface are scored separately, so the grade on the label can be explained rather than just accepted. Every grade we issue goes into our Population Report, where anyone can see how a card sits against every other copy we've graded.
We grade cards and nothing else. We don't buy, sell or deal, so we hold no position in anything that passes through us and nothing to gain from a grade landing high or low. Every card is held to the same standard.