When hiking, you may encounter a gate across your path. Whether open or not, the common action is to close it after passing through.
Maryann, the rancher I met yesterday, taught me that is not the correct thing to do. Sometimes, hikers may accidentally leave a gate open instead of closing it. If that happens, then livestock may escape and run wild. The rancher then has to round up the strays - a real hassle.
But if a gate is closed when the rancher wanted it open, livestock may be denied access to vital water and die.
So, leave open gates open and closed gates closed once you pass through.