Two common terms you’ll hear when discussing any robot arm will be robot accuracy and robot repeatability. 

Accuracy is the difference between what you asked the robot to do, versus what it actually did.  For example, if you asked the robot to move to a point 10 cm away from another point, how close does the robot get to that 10 cm destination?

Repeatability (or precision) is the ability of the robot to repeatedly execute the same task.  For example: if you teach a point and tell the robot to go there over and over and over again, how close to that taught point will it be each time.

Commonly, industrial robots are intended to be repeatable (precise) but not necessarily accurate.