What does 4 rings then voicemail mean?

I’m trying to get in touch with someone but everytime I call, the phone rings 4 times then goes straight to voicemail. I doubt they’re ignoring me because it cuts off at exactly the same place everytime and goes to voicemail. Usually there’s 5 or 6 rings, not 4, so what does this mean? The rings sound a little choppy and staticky. This person is in Florida and I’m in New York. We both have Verizon. Could they not be getting service? Or maybe their phone is dead? I’m just a little worried.