From my experience I always worked at companies in which the Sprints started on Mondays and ended on Fridays (regardless of the sprint size, obviously). Is there any good practice that says this is the best period to work on a sprint?
It seems to me that having the last day of a sprint on a Friday makes things harder, as people in general are already thinking on their weekend plans and the sprint is in its last steps to be delivered successfully, which could ask for some extra focus.