Pretty annoying when I don't finish a sentence, isn't it? Incredibly, that's how many reporters these days finish up a story.
I cannot tell you how many stories I've seen that end with a soundbite followed directly by a tag-out. And when you end a story that way, you've basically given the viewer a package without an ending.
(On the other side of the coin, we have the "opening-line-of-the-package-is-the-same-as-the-lead-in syndrome, but that's a topic for another day.)
Stories need an ending that wraps up what the viewer has just seen, and that is best provided by a line or two of voice track. When you end a package on a sound bite, and then tag it out (probably because you can't think of anything else to say) it's jarring to the viewer.
Imagine fairy tales without "and they lived happily ever after." So Prince Charming put the glass slipper on Cinderella's foot. The End. If you were reading the story that way to a kid, the child would ask, "And then what happened?"
Think of it as a "cool down"
When you reach the end of your script, you need to look back at the whole thing and come up with a few words that sums up the package. Tie it all together in a smooth manner, then tag it out. Your packages will have a smoother flow and feel more comfortable to the viewer.