This testing works well for comparisons, but it is far from a comprehensive assessment of a VPN's overall performance. So many factors can affect network performance, from the time of day to the individual configuration of VPN servers that I cannot account for all of them. Therefore, it's useful to think of these results as a snapshot of performance.
Someone turns their computer into a network access point, and gives is a real-enough sounding name (often imitating popular, well-known ones like “T-Mobile” for instance). When you connect, you’re actually connecting through their computer. And they now will gain access to all of the information you used to login, as well as your browsing activity.