When whisking egg whites, it is very important that the bowl you are whisking the egg whites in, is very clean. The bowl should not have anything else other than the egg whites. Or else the whites will not stiffen up and it will just be liquidish no matter how long it is beaten for.
So a note to self, ‘Do not be lazy and clean the bowl before putting the whites in’
If the egg whites are not at the consistency that is requited, the cake will not be fluffy and soft. The cake will be flat and wrinkle-like.