When I see that on a plant, it's usually caused by having been too dry. The dry spell may be a week or so before the evidence shows up in the leaf tips. Maybe it was allowed to get too dry before you acquired it? Or maybe it's an adjustment to a change in the amount of moisture between environments? Changing the environment causes a lot of foliage to be affected. I see a lot of it every year when I move things inside for the winter or back out for the summer. The difference in temperature, light, air circulation and humidity always cause some of the plants to react. Usually by dropping old leaves and growing new ones which are adjusted to the new environment. Except for that brown tip, it looks healthy otherwise. I don't have a lot of experience with hostas, though. They aren't too common in my part of the world. I'm having some success with one now that in it's third year here.
