Managed shared hosting is often the best starting point for business websites because infrastructure administration is handled for you. A Cloud VPS becomes useful when you need more predictable resources, custom software, root access or isolation from other workloads.
What to consider
Common upgrade signals include sustained CPU or memory pressure, application requirements that are not supported on shared hosting, higher database demand, custom background workers or stricter security controls.
Before upgrading, measure the current bottleneck. Moving to a VPS will not automatically fix inefficient application code, but it does give you more control over resources and system configuration.