The lighting of a photo can determine the mood of the portrait, and therefore you will need to pick one, and actually, pick the right one.
You can basically start with whether you want a bright or dark portrait first, and then fine-tune the degree of brightness in the category you want. Whether or not the clients want a bright or dark lighting may due to different factors:
- Well, what the portrait is for
- Their mood
- What they want to present in the portrait
- Their personality
- Of course, the background lighting will also be a factor
