Homelink does the auto open/close based on the GPS location of your car, and that isn't accurate down to inches.
Now if you manually close the garage door using homelink (not automatically based on your location), then it will also close it from anywhere, no matter how close you are (even inside the garage) or if you are across the ocean in Japan, as long as the car has a solid wifi of cell signal connection.
In my case, our first half mile drive from the house is a dead spot with no connection. So homelink always lost it's connection when I drove away, while being in the "garage closing" state. Unfortunately, homelink could pretty much never recover from that, I call it a bug in their software. It would show "garage door closing" forever, and then act erratically at times. Including two times when homelink was so confused about the state of the garage door that it opened it when I was miles away. It probably just sent another "close garage door" signal while being confused, and since the homelink module is operating no different than a clicker, the "close" signal is actually an "open garage door" signal when the garage door was already closed.
It was frustrating, not worth my time and an open house whenever homelink was in the weeds, LOL.