Poor drainage would be any container without a hole in the bottom. As long as excess water can escape, it drains. Whether or not the soil has air in it while moist is another matter, regarding the soil texture. If roots have only moisture but not oxygen, they can't function, and rot is the usual result. Using only larger particles, eliminating tiny particles like sand, silt, clay, peat, is the easiest way to accomplish that. And not packing soil tightly into containers, or using a strong gush of water that compacts soil.
Which way does the window face?
