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I find the name "Bounded Accuracy" confusing. Bounded - Ok limitations, sure, but Accuracy - maybe because it limits how often a give roll is successful for higher vs lower level PCs, but not every skill check is about being accurate. Many are about lies or deceit and deliberate inaccuracy. It sounds like it should just be called a power cap.

My question is: How can I relate the term Bounded Accuracy to its meaning?

Accuracy refers to the percentage chance that a given attack will hit. An attack may have high accuracy or low accuracy, but both of these are a measurement of accuracy.

It's a little awkward to use the word accuracy to include things that we don't normally think of as a "hit", such as a skill check, but it makes more sense if we remember that the DC of a roll is what's called its "target number", as per PHB p.7:

3. Compare the total to the target number. If the total equals or exceeds the target number, the ability check, attack roll or saving throw is a success. Otherwise, it's a failure. The DM is usually the one who determines target numbers and tells players whether their checks, attack rolls, or saving throws succeed or fail.

The target number for an ability check or saving throw is called Difficulty Class (DC). The target number for an attack roll is called an Armor Class (AC).

In earlier editions of D&D, particularly third edition, numbers could get very high where high-level or highly-optimal characters with a lot of stacking bonuses were involved. A roll could be almost impossible for one character and almost guaranteed success for another.

Hence bounded accuracy, where the range of numbers it's possible for a character to roll is kept within tighter limits, or bounds. This shifts the focus of the game away from character optimization (by stacking small bonuses), and toward interacting with the fictional world by searching for in-situation ways to acquire Advantage.

The earliest reference to 'bounded accuracy' as a D&D5e concept I've seen was in this Legends and Lore article of the same name by Rodney Thompson (former WOTC employee, credited with, amongst other WOTC products, Rules Development on the 5e PHB).

While the whole thing is worth a read, here are some of the important bits:

The basic premise behind the bounded accuracy system is simple: we make no assumptions on the DM's side of the game that the player's attack and spell accuracy, or their defenses, increase as a result of gaining levels. [...] Characters can fight tougher monsters not because they can finally hit them, but because their damage is sufficient to take a significant chunk out of the monster's hit points; likewise, the character can now stand up to a few hits from that monster without being killed easily, thanks to the character's increased hit points.

[...]

Now, note that I said that we make no assumptions on the DM's side of the game about increased accuracy and defenses. This does not mean that the players do not gain bonuses to accuracy and defenses. It does mean, however, that we do not need to make sure that characters advance on a set schedule, and we can let each class advance at its own appropriate pace. Thus, wizards don't have to gain a +10 bonus to weapon attack rolls just for reaching a higher level in order to keep participating; if wizards never gain an accuracy bonus, they can still contribute just fine to the ongoing play experience.

[...]

This extends beyond simple attacks and damage. We also make the same assumptions about character ability modifiers and skill bonuses. Thus, our expected DCs do not scale automatically with level, and instead a DC is left to represent the fixed value of the difficulty of some task, not the difficulty of the task relative to level.

My takeaway from this article is that the focus of the 'bounded accuracy' design philosophy seemed to be on not making hit chances and defenses scale by level to the point where level differences trump all else, and that new philosophy extended to how numbers scale with level throughout the entire game beyond just hit chance and AC, with the name simply sticking.

Ultimately, that name stuck because, so far as I'm aware, it's one that WOTC themselves penned to refer to that part of 5e's design.