Cybersecurity is an essential field in our increasingly digital world, dedicated to safeguarding the integrity of networks, systems, and data centres. Among all cyber security practices, Pentesting or Penetration Testing, possesses a unique significance.

Pentesting is an authorized and procedural attack on a computer system, conducted to assess its indestructibility, identify vulnerabilities, and determine whether unauthorized access or other malicious activity is possible. Far from being destructive, Pentesting forms a crucial segment of assembling resilient online infrastructures and applications.

The cybersecurity universe segregates Penetration Testing into three distinct types: white-box testing, black box testing, and grey box testing. White-box testing gives the tester complete information about the system being tested, equipping them with extensive knowledge about the internal mechanisms. Black-box testing, conversely, provides no preliminary information about the system to the tester, thereby mimicking a real-world external hacker attack. Grey-box testing, as the name suggests, is a blend of the other two, where limited information is given to testers, emulating the perspective of an inside attacker.

The penetration testing workflow encompasses five cardinal stages. Initially, the planning and reconnaissance phase includes defining the scope and goals of a test – harvesting intelligence such as network and domain names. Subsequently, scanners are used to comprehend how a target responds to intrusion attempts during the scanning phase. The gaining access and maintaining access phases involve exploiting vulnerabilities found during the second phase to break into the system, staying long enough to produce a significant impact. The final phase of pentesting called analysis, sees the tester interpreting the results from the penetration test and documenting all procedures, findings, and recommending strategies to mitigate identified vulnerabilities.

The motive behind conducting a penetration test can be multifold. While organizations are generally obligated to protect their user data, pentesting aids in identifying 'weak spots' in their security posture. It also provides an organization with a realistic overview of its current security stance, enabling the creation of an actionable remediation strategy. From a more regulatory perspective, Penetration Testing is also often a prerequisite for compliance with standards such as the Payment Card Industry Data Security Standard (PCI DSS).

In conclusion, the necessity for a robust cyber security framework cannot be understated in today's digital age, and Penetration Testing forms a vital cog in that wheel. It is the first line of defense in preparing systems against genuine threats, fortifying them against potential abuses of vulnerabilities. Despite the advances in technology, the axiom 'Offense is the best form of defense' holds equally true in cyberspace as it does in the real world — calling for the need for knowledge and execution of efficient penetration testing strategies.