Generally, suitable hair style depends on lifestyle, color of eye, color of eyebrow, color of hair, color of skin, clothes, height, occupation and interest.
Therefore, there is kind of formula.
I agree, but honestly, I don't know. Suitable hair style is sort of criticism, evaluation, consensus. How a majority of people who are close to you think of that. However, their opinion is totally inconsistent. Especially, creative hair style or unique and crazy clothes. With the advent of new style, a majority of people have negative point of view. Maybe it's too early? Adherence to the fixed idea? I guess that is true. We can't complain about it. But I don't like it. So suitable hair style could be very simple, conservative, and boring.
In conclusion, I think there is no unsuitable hair style. Everything will suit you. How you feel is a vital. and also, how you manage is important.