One of the best ways to understand what is going on is to go to the Gemba and see for yourself. This is the central idea behind the term Genchi Genbutsu, which is a core principle in both Lean and Six Sigma.
Genchi Genbutsu (English: Go and see for yourself): The best practice is to go and see the location or process where the problem exists in order to solve that problem more quickly and efficiently. To grasp problems, confirm the facts and analyse root causes.
Reference - Toyota Blog
Both Lean and Six Sigma require a sound understanding of issues and opportunities before moving forward. Whether management, leadership or shop floor Genchi Genbutsu supports correctly understanding a problem in its entirety before coming up with countermeasures. The nature of the phrase is less about the physical act of visiting a site but more to do with a personal understanding of the full implications of any action within an environment as a whole.