When a single point is selected the precision may be shown. The precision values are in the same units as the x,y,z positions. Approximated points do not have precision values displayed because precision calculations depend on 3D processing.
These precision values are one standard deviation based on the post-processing covariance matrix of the 3D object points. These precision values give a 68% confidence interval for that point (i.e. a 68% probability that the true point falls within the area defined by the precision numbers).
For further discussion of the meaning of precision refer to Accuracy and Precision in the Glossary.