Default Siemens NX setting for sketch origin is a “specify point”. It makes sketch origin to the nearest point that selected surface.
For arranging the origin of the sketch to work part origin; Click <Specify CSYS> drop-down menu and select use <work part origin> from the menu. The origin will change as the picture shown below.
For changing default settings for sketch origin. Change go customer defaults and change sketch origin as a project work part origin
Customer defaults => Sketch => General => Session Settings => Project work part origin
