This is because it allows editors to move clips around irrespective of time order (non-linear time), in contrast with linear editing [1] where you build an edit

This is because it allows editors to move clips around irrespective of time order (non-linear time), in contrast with linear editing [1] where you build an edit by assembling the master in sequential order (ie, by recording from one reel/tape to another). [1] https://en.wikipedia.org/wiki/Linear_video_editing https://en.wikipedia.org/wiki/Linear_video_editing