When operated correctly a rowing machine can be one of the best pieces of equipment in a gym, using lots of different muscles and providing a hard workout which will see you burning fat and replacing it with muscle.
Unfortunately this guy isn’t operating the rowing machine correctly. In fact, he’s doing such a bad job with it this video could be used as an instructional video of what not to do.
Your arms are meant to do most of the work while rowing, your legs and stomach muscles helping out to. This guy is all about the legs, not using his arms at all.
It ends up with him looking like he’s having sex with an imaginary woman sitting open-legged at the front of the machine. That would also provide an intense workout, but wouldn’t really be appropriate in a public space.