Some rather flippant dismissal going on in the other comments here. The reasons that this sort of things is frowned on by corporate governance are firstly the

Some rather flippant dismissal going on in the other comments here. The reasons that this sort of things is frowned on by corporate governance are firstly the non-merit-based promotions that happen, and secondly the power imbalance. It's a reputational risk for the corp. Especially with women in lower positions on the org chart and men in higher ones, there is a risk of coercion if intimate relationships are allowed.