Which is the most powerful VPN in the world?

Could you elaborate on what makes a VPN powerful? Is it the speed, security features, number of servers, or user privacy policies that determine its strength? Additionally, how do we accurately compare and rank VPNs worldwide to determine the most powerful one? Considering the ever-evolving landscape of cybersecurity and VPN technology, is there a definitive answer to this question, or does it depend on individual user needs and preferences?