>>20961563If we are talking pre XY then it's probably because you have a full team of pokemon that need equild training. If you want to be same lv as elite 4 and stuff then a party of 3-4 is the most optimal.
I don't know what you problem is if we are talking XY tho, exp. share is ridiculous, you can use 1 pokemon the whole game and your party would be the same lv
