Product review (5 stars): It wasn't working, but I'd still find myself standing at the fridge, pressing my cup into the paddles like a doofus...
When the water dispenser in our Samsung fridge decided not to turn off, we thought at first that it was the switches...and one of them actually did test out as bad.  But when replacing the switches didn't fix the problem, we headed upstream and discovered that the problem was *actually* in the valve assembly.

It was a quick swap out and we have filtered water and ice again!