Better technology, better pictures
As technology improves, the ease to take better and nicer photographs speeds up quickly.
With nikon d300's 3d tracking, 51 point area focusing, its sometimes quite hard to miss a moving object. The success rate is high and it gives you, as the photographer confidence
With a higher success rate, it translates to lesser wastage of unnecessary shutter counts (that is depreciation which is a cost!)
I'm no spokesman for nikon but a camera like this has definitely eased my worries of getting lousy pictures for stock.
Photo credits: Koh Sze Kiat.