Direct answer
Problems diagnosis and verification are useful when you suspect your VPN on macOS is not working as intended—such as when connectivity is unstable, sites misbehave, or you want to check that traffic is actually going through the VPN. They are less useful for making strong guarantees: verification cannot prove “complete” anonymity, overall safety, or guaranteed access, and results may vary with your network, device state, location, provider, and time.
What “problems and verification” mean on macOS
In this context, “problems” are symptoms like repeated disconnects, apps bypassing the VPN, or unexpected DNS/website behavior. “Verification” means running practical checks to see whether the VPN is functioning as you configured it—before relying on it for privacy-minded browsing, anti-tracking efforts, or day-to-day work while traveling.
A simple mental model: diagnose first (is the VPN connected and configured?), then verify key expectations (does traffic routing and name resolution match what you intend?), and finally re-check after changes (Wi‑Fi switches, travel, OS updates, app reinstallations, or configuration tweaks).
How it works (a simple model)
A VPN on macOS typically creates an encrypted tunnel and routes your device’s traffic through a remote network endpoint. If routing, DNS resolution, or app-level settings don’t align with that goal, you may see leaks or unexpected behavior.
Verification helps you catch mismatches between intention and reality—such as the VPN being connected but not covering the traffic you care about, or name resolution behaving differently than expected after network changes.
Operating conditions that affect usefulness
Problems and verification are most useful when conditions are likely to change: international roaming, switching between Wi‑Fi networks and mobile hotspots, changing VPN protocols/settings, or updating macOS. They’re also useful when different apps on your Mac behave differently (for example, browsers vs. system services), because you may need to confirm behavior across the software you actually use.
Main limitations to keep in mind
A VPN does not guarantee anonymity, safety, or access. Even a “good” verification outcome only indicates that certain checks look correct at that moment; it does not eliminate all tracking possibilities or all risk.