That depends on the box set:
- Is it a series by a single author?
- Is it a multi-author series?
- Is it a group of unrelated books in the same genre?
I will almost always read the entire box set if it is a series by a single author. If so, I’ll then review the whole box set (although my review may focus more on the first couple of stories, as giving too much detail about later stories could be providing spoilers).
I will usually read all the books in a linked multi-author series, such as A Louisiana Christmas or A Tuscan Legacy. I may or may not read all the books where the stories are linked. I will therefore review the stories I’ve read.
In case you’re wondering, the Trinity Lakes Romance series is linked by a common location and some common background characters, and each story is designed to be read as a standalone romance. However, Trinity Lakes isn’t available as a box set.
If the box set is a collection of unrelated titles by different authors in the same genre (e.g. a compilation of rom-coms or a compilation of suspense stories), then I may not even read all the books.
Even where I do read all the books in a boxset, there is always one or two I enjoy more than the others, and one or two I don’t enjoy enough to finish. My review naturally focusses on the books I enjoyed most.