Three-dimensional (3D) imaging systems and methods are disclosed for analyzing idle time duration in a storage area. A 3D-depth camera non-concurrently captures frames having respective 3D image datasets. A 3D data analytics application maintains a plurality of records including a first record, associated with a 3D image dataset of a least-recent frame in a series of frames; a third record, associated with a 3D image dataset of a most-recent frame in the series of frames; and a second record, associated with a 3D image dataset of an intermediate frame captured between the least-recent frame and the most-recent frame. Based on comparisons of the first, second, and third records, an activity status type is determined defining an activity occurring within the storage area during a particular time segment. A cumulative idle time duration is incremented based on the activity status type having a non-loading status type.