In broadacre dryland farming your yield potential is fixed before the first seed is sown and every decision you make will likely reduce it, the only question is by how much. As a crops yield potential is dictated by rainfall in crop and how much rain is captured in the the fallow.
From there the best we hope to do is maintain that yield potential. The way we do this is by maintaining good stubble cover and having good fallow weed control to increase our fallow efficiency and store as much moisture as possible. Through checking soil nutrient levels and using fertiliser to ensure no nutrient is lacking. Sowing accurately and on time to ensure you have a good plant stand and the crop will be flowering in the right window. Controlling weeds, pests and disease in crop to minimise stress to the crop.
If all of these are done correctly the crop will be able to get as close to its moisture limited yield potential as possible.