In my case this was an aisle with kitchen products on one side and children's toys on the other. I said that it seemed a bit strange to have these two things together, and maybe the aisles could be rearranged so that eg. the children's clothes were next to the toys. I also said that some of the stock could be replenished and the items could be neatened on the shelves. She asked if I thought there were any positive aspects to the aisle and I couldn't think of anything...I probably should have said something like 'it's colourful'.
I talked about wanting to bring my experience to a retail environment, and also said that I liked the Boots mission of helping people feel as good as they can, and their commitment to sustainability which they claim on their website.
I would recommend choosing something that you have used or that is similar to something that you have used so you can talk about your personal experience. I went into how the product works and I also mentioned that using it made me feel more confident which I tied to the aim of the Boots brand of making people feel their best, which the interviewer seemed to like.