Flat bottom woks need a lot more oil to stir fry properly, due to the lack of pooling. Flat bottom woks on electric cooktops (radiant or induction) also tend to have essentially nonexistent heating of the side slopes, preventing you from using the technique of splashing soy sauce (and other cooking sauces, as well as cooking wines) in a wide arc so that it reduces rapidly to form a sticky coating for the food. Instead, all of the sauce will just run down to the bottom where it joins the rest of the liquids coming out of the food, contributing to boiling/steaming rather than stir frying.