KJV only: Why?

I’m Protestant, but I’ve never ran much into the KJV only crowd. Luck of the draw I suppose, but I’ve seen a few lately and it’s made me wonder. Where’s that come from and what’s the appeal of it? I personally find that translation’s archaic language to be a downside, but some people seem to think it’s the one true translation.

I just don’t see the point, especially in an age where we can compare so many good translations side by side.