This type of testing is based on the method, when intruder attacks not your information system, but an ordinary employee of your company, so it is called social engineering. This method of unauthorized access to information or data storage is carried out without using of special technical means, as it is entirely based on the human factor.
You say, "What's my business with it?", But it should be borne in mind that the most destructive penetration occurs precisely on the principle of social attacks. Thus, the cyber-criminal can save a lot of time to gain access to your system, because well-built dialogue by any communication mean may give him access password just in a minute.
Our social engineers have a huge number of tools, including those developed within the company, as well as scenarios for the successful attacks, enabling find a gap in the system and to prevent such attacks in future.