The Latest in Robocall Tech: Nothing

Quick question for the hivemind. For the past month or two I’ve been receiving a lot of very strange phone spam. The phone number is always from my local area code, but it changes with every call. What makes the calls weird is that there’s no recorded message and no human being on the other end of the line. If I wait for a while, it hangs up. I get these three or four times a day on my landline and, more recently, two or three times a day on my cell phone too.

Is this the latest in annoying robocall tech? What’s the point? Why is someone spending money to call people and then do nothing? Is anyone else getting these calls?