Curating group shows could, at first pass thought to be an easy task. Collect the best work that you can find from all the participants, and install, this oddly enough, is perhaps not the way to go. It can create an overwhelming experience, a bit like overload, with no resting space. The fact is strong work can easily sit alongside work of a slightly lesser quality. This is precisely what makes an exhibiton work, it allows all the work to breathe, and to visually interact with each other. This approach elevates all the pieces in the show, and gives the audience some work to do, rather than feeling force fed.
Curating and installation requires a visual packaging skillset, how to group, not necessarily images that are just visually similar, but also being about images that are contextually linked. All artworks about journeys, lets say, will be approached by each artist in a very different manner. The skill to connect these images in a space is clearly the curator, they have the experience to be able to pull a show together.