Why is a penetration test considered to be more thorough than vulnerability scan?

Vulnerability scans perform far more than host discovery and port scanning - they actively probe services for known CVEs, misconfigurations, and software weaknesses.

A penetration test includes an active exploitation phase where testers attempt to leverage discovered vulnerabilities to gain unauthorized access or escalate privileges, demonstrating actual risk. A vulnerability scan only passively identifies and catalogs potential weaknesses without confirming exploitability, making the penetration test a more comprehensive and thorough assessment.

This reverses reality - vulnerability scans are typically automated, while penetration tests rely on skilled human testers who manually analyze systems and chain exploits together.

Tool comprehensiveness is not the defining distinction; the fundamental difference is that pen testers actively exploit findings rather than just reporting them.