I previously would use this all of the time alongside “If” to check whether or not there was anything coming from the Share sheet (1); if not (0), then I’d use Get Clipboard.
This technique makes shortcuts work from both the Share sheet or from the widget/Siri using something you grabbed with copy & paste; however, in iOS 13, the “If” action was updated to include “If [Input] does/does not have any input]”, making this technique unnecessary. It was confusing to explain, so I am glad to reduce the number of actions I use and not include Count all over the place.
However, I still do use it to check whether there’s 1 or more, so it’s not totally out of use.
I also take advantage of Count for Words for estimating how long articles will take to read, Characters for making sure my tweets don’t go over Twitter’s limit, and in other scripting situations.