An IT environment of a kind, from basic internet access and e-mail to fully working cloud and web-based applications will be created for each organisation, often processing sensitive or invaluable information. Any compromises of these systems not only involve breach of the network but also risks unauthorized data access.
If you want to understand more about the vulnerabilities that can possible hit your network(s), the best way is to run a simulation of a real-life attack that tests the effectiveness of your security controls. A Pen Test does exactly the same it involves attack simulations that violate security controls rather than addressing specific vulnerabilities. Penetration testers use a toolkit that includes manual Pen test tools and automated vulnerability scanning tools to detect the gaps in your enterprise applications, Web applications, and network infrastructure.