Credit is an important concept to grasp in BA. The longer the flight, the more credit the trip attracts. Given that each month you need to hit the credit target (or have enough bank to cover the deficit) that makes shorter trips fairly unpopular. Few people - perhaps except those with specific reasons (upcoming command, friends & family downroute etc) would bid for stuff like EWR/YUL etc out of choice. You’d just be choosing to do more days at work for no additional credit.