Verizon says a software problem caused the glitch and it is conducting a postmortem, but experts say outages are "a fact of life" these days.

Some Verizon customers went without cell service for over seven hours on Jan. 14. Here's what we know about the cause of the outage.

The outage, which began Wednesday afternoon and dragged into the late night hours, triggered a flood of complaints from coast to coast.

Lee McKnight, a professor in the School of Information Studies at Syracuse University, said that 5G networks increasingly run on hundreds of cloud services — along with cell towers and fiber wires — that operate in tandem, require constant updates and are subject to software hiccups that can ripple through the larger network.

The outage's only close contender in the worst cell service implosion of the 2020s would be the great AT&T nightmare of Feb. 2024. That one also lasted roughly 11 hours; a later investigation revealed 92 million calls didn't go through, including 25,000 calls to 911.

By now, you've no doubt heard about (or experienced yourself) yesterday's massive Verizon outage. For nearly all of Wednesday, roughly two million Verizon customers could not connect to the network, and had to rely on wifi to use their smartphones, which were otherwise stuck in SOS mode. Sure, they could call 911, but they couldn't do much else.

During the Verizon outage, police warned that contacting 911 could be tricky. Big disruptions can have cascading effects on everyday life.