"Rich people can afford a luxury" is obvious enough, but how rich did you need to be to hire that specific artist? Was Sargent knocking out two portrait a day for every local dentist or was this a one-off where the offer was simply too good to turn down? It'd be cool to know....
And of course, "commissioned by her father, a local merchant" is kind of interesting and it's even more interesting when it's not the case.
This is basic knowledge.