Typically, a walk in interview strategy is used to conduct interviews when the recruiting firm is wanting to hire in huge numbers. Or are so desperate for good people that they are ready to scan anyone who can 'walk-in'. The number of rounds of an interview generally remain the same.
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A lot of companies these days entertain walk-in interviews where candidates can simply reach the office, and get interviewed by the employer on a specified date and time. Walk-in interviews give opportunities to a lot of people to apply and get interviewed. It also saves the company time, when they are in urgent need of conducting a process with many people.
In HR such kinds of interviews happen on a regular basis, these are scheduled without any prior appointment. These interviews have the following features:
1. Happen without any prior appointment.
2. It's a kind of meet and greet session, which is of very short duration.
3. Comprises of very few questions.
4. Used as a quick tool for narrowing down the talent pool.
5. It's spontaneous and unplanned but structured.
6. Used by companies when they want to do mass recruitment, especially useful for initial screening.
A walk-in interview is a job screening that happens without an appointment or scheduled meeting. They are common at career fairs and informal meet-and-greet sessions, and they tend to be relatively short and often consist of only a few questions. Employers may offer candidates a job at the end, but more often than not, the meetings are used as a way to quickly narrow down the applicant pool. Top candidates are often invited for a more formal interview at a later date.
Source:- https://www.quora.com/What-is-a-walk-in-interview