If the company lacks either, or either gets too much power they are in trouble. Creative types will spend too much money on things that are nice but won't deliver enough value and so the company goes bankrupt. Financial types don't understand what customers want and optimize away all the expensive creative value the customers buy.
Note that the above applies to every type of company. Exactly what "creative" means is different for different industries, and some need it more than other (how much innovation do you need in soap?...). It always applies though so you need to ensure you get both types in leadership positions even though they don't like or understand each other.