We use VPNs a lot these days, both on a business and personal level.
As a company, in order to facilitate employees to work remotely, they often provide VPNs based on commercial companies such as Cisco. As an individual, for convenience, most scenarios may also choose a mature third-party VPN provider.
But sometimes we may already have our own VPS, or a third-party VPN cannot meet our demands in some aspects. At this time, it is also a common choice to build a VPN based on VPS. Of course, there are also many people who simply feel that they are happier with their own hands. XD