A reset means the conversation started, then one side slammed the phone down. The server accepted the connection, but something (the server itself, a firewall, a VPN, or the network in between) forcibly closed it before the page finished loading. Unlike a refusal, the door opened; it just did not stay open.
A reset seen by every visitor usually means the application is crashing or restarting mid-request, or a load balancer is killing connections it considers idle. Check the application and proxy logs at the exact timestamp of a reset, confirm keep-alive timeouts on the proxy are not shorter than the backend expects, and check for out-of-memory kills on small instances. End users cannot fix a server that resets them; the evidence to hand the operator is the time, the network, and whether it happens on every device.
If resets hit many unrelated sites from one machine only, suspect that machine: a failing network adapter, stale drivers, or malware tampering with the connection. If they hit everyone on one network, the router or provider is resetting, and the phone test is what proves it.
What is the difference between ERR_CONNECTION_RESET and ERR_CONNECTION_REFUSED? Refused means the connection was never accepted at all, an immediate no. Reset means it was accepted and then cut off partway through, so the causes differ: refusals point at closed ports and firewalls, resets point at crashes, middleboxes, and unstable sessions.
Can a website reset the connection only for me? Yes. Web application firewalls and rate limiters reset connections from addresses or regions they distrust, and a VPN exit node with a bad reputation triggers this often. Loading fine on mobile data but resetting through a VPN is the classic signature.