Understand the idea
Comparing two connections can help identify a network-specific issue. It is a diagnostic comparison, not proof that either provider is universally better.
Put it into practice
Open the same public page over Wi-Fi and mobile data, noting time and error messages. Consider data charges before downloading large files.
Know the limits
Do not switch networks repeatedly while an account or payment request is still processing.
The wider context
Connection tests are most useful when they are repeatable. Compare similar conditions and record the time of a problem. Faster networking can improve responsiveness, but it cannot create reliable returns or change the rules of an online activity. Avoid tools that require unnecessary device access.
Your next step
Use the practical step above only where it fits your situation. Before an account-specific action, check the current instructions from the service or device provider involved. Write down what you observed and what remains uncertain; that makes a follow-up question more useful.