A VPS gives dedicated resources and root access. It also transfers server management to you unless bought managed.
WHEN IT IS THE RIGHT ORDER
You need root access or custom server software You need specific system packages or server-wide configuration You have genuinely outgrown shared or reseller limits An application requires persistent background processes
WHEN IT IS NOT
A slow site that has never had caching enabled A vague preference for dedicated resources
WHAT TO DECIDE BEFORE ORDERING
Managed or unmanaged. Unmanaged means you handle operating system updates, security patching, backups, monitoring and configuration. That is real ongoing work requiring real knowledge. Whether you need a control panel, which usually carries a licence cost.
Resource sizing: CPU, memory and disk.
AFTER ORDERING
Provisioning may take longer than shared hosting, and initial setup is yours unless managed.
BEFORE COMMITTING
Open a Sales ticket describing what you intend to run. We will tell you honestly whether a VPS is needed, and whether managed or unmanaged suits your situation. Quite often the answer is that shared hosting plus caching solves the problem.