Price used to be a reason. Now spec levels (and prices) are nearing that of the competition,
Zetor gets compared to them as well, so in the end the better marketing of the big brands convince the customers.
Without a 200hp tractor with semipowershift, dealers arent going to invest in branding, because Zetor offers so little in return: All the big brands now offer economy dairymen tractors, which was once Zetors unique selling point.