As you have seen in recent posts, I often do portraits in black and white. It’s just better that way in portraits: distractions (like colourful clothing) are removed.
But sometimes you have to recognize that colour is called for. Like in this shot of the same model:
I mean, that screams colour, doesn’t it? When a shot has prominent colour like that, use that colour.
As does the following shot, because of the matching cool glasses and Ralph Lauren tie. If we did not use colour here, that match would be lost.
That reminds me: Props are important.