I've always thought we are more likely to comment when something
unexpected happens - so when you call a company up and they do exactly as you ask, it is unremarkable because it's what you expected them to do. But if they lie, fob you off or generally mess it up, you are more likely to comment (or set up a website

) because it is not what you expected them to do.
When people (such as the ntl people here) go above and beyond,
that's when I tend to sing their praises.