Here is a good example of how a picture like this might come out once vectorized. Photo quality images will always look different once vectorized, but the artist has used different effects including bitmap effects to replicate the original as close as possible. There are various reasons people have this service done, such as: printing purposes; they like the style/look of the vector art; it is easy to manipulate; etc.
If you have a photograph (of a person or otherwise) that you would like to get vectorized it is always best to get a quote first.
You can upload a quote for a speedy and efficient process here: Here (no account required). You can also email us with any questions: firstname.lastname@example.org