Every single day thousands of people applying for jobs. Because of the increasing population both of the job advertisements and number of applicants are increasing together. There may be hundreds of applicants for same open role. Consequently, ıt becomes difficult for the employer to select people and for the candidate to get a job. Therefore, in addition to technical questions employers can ask candidates personal information such as their hobbies, interests or about family life for selecting the appropriate person for the role.
First of all these answers can be useful for employers. Because based on these answers employers can make personal assumptions. For example, a person with good social life can be a better team member compared to a less social person. Another example is a single person can focus the work easily compared to a person with a family and a child. All of these factors are important for the employer for trying to select the right person.
On the other hand, with candidate perspective these types of personal questions can be irrelevent. Because the answers can be private. Also, a candidate may not want to share these information with a stranger. In addition, they can think that these questions are not relevant to position which they applied for. It may not be correct to make general assumptions according to these answers.
In an interview candidates may have to face personal questions besides technical questions about the work. Depending on different perspectives, these questions can be said to be both relevant or irrelevant. It depends on the persons role, employer or candidate.