In the environments that I worked in (2007-2015) staging was more of an environment for security and performance testing. My past QA environments were enough li

In the environments that I worked in (2007-2015) staging was more of an environment for security and performance testing. My past QA environments were enough like production to make functionality testing there practical. The only other environments that I dealt with were more like demonstration environments, where the CEO could show off new functionality to key customers or investors. I'll highlight that containers hadn't really taken off then, and the companies I was part of were small (VC round A through D).