confused!

For my understanding visa is for the entering US, and your status depends on your I797 form. What is the relationship between expired visa stamp history with your current status? Even if you don't have a expired H1visa stamp, you are still in H1 status, even if you are outside of the country. Or if you will lose your h1 stauts if you go out of US, how could the expired visa stamp help?
just dicussion, you guys are really helpful!