OGL isn't a junction, no once mail/express train originating/terminating from/to OGL, earlier only 2 pairs of MEMU that operated by BZA & GNT that is not rested at OGL.
While NZB is a junction & converging station.
ADB-HYB line,MMR-HYB line,BDHN-HYB line,KRMR-HYB line connected here,in future ARMU-ADB line will be completed.
Earlier NZB have more than 50 halting trains& 9 pairs of trains were originating/terminating,...
more... such are NZB-PUNE pass,NZB-PVR pass,NZB-NED pass,NZB-KCG pass, NZB-KRMR DEMU,RAYALASEEMA SUP EXPRESS, trains occupied platforms ,need shunting & loco reversal, Moreover NZB hasn't chord line for goods train so 4-5 platform need.