You have a 3 gallon jug and 5 gallon jug, how do you measure out exactly 4 gallons?
If you knew that, you've answered one of the Google's brainteasers questions, and would have made a huge stride towards starting a career at a technology behemoth. Google was smart enough to know the ineffectiveness of these brainteasers in interview, hence they banned the practice a few years ago.
Google came to know that these brainteasers are not suitable to predict the performance of a candidate on an actual job. These tests hardly ever give any meaningful insights into the dexterity of candidates. In fact, there are other better determiners that can be put to use to gauge the technical skills of a candidate.
Predominantly, brainteasers evaluate how good applicants are at swiftly coming up with a brainy and erudite solution to a hypothetical problem under pressure. But, candidates don’t experience this artificially created on-job pressure in the actual work.
In fact, candidates have to go through stressful and abstract task that is completely irrelevant to the real on-job experience. Asking brainteasers in a technical interview is just to make an impression that speaks highly of an interviewer. These questions don't results in valid and intelligent outcome.
Instead of determining how someone will perform on relevant tasks, the interviewer measures how the candidate will handle a brainteaser during an interview, and not much more.
Generally, interviews pose a particular challenge when it comes to predictive validity—that is, the ability to determine someone’s future performance based on limited data.
This phenomenon is commonly known as “thin-slice” judgment. First impression is of prime importance. Once formed, they paint the rest of interview with the same color. The exact same interview response given by two different candidates, one of whom the interviewer preferred, would be rated differently.
What is the best course for the the companies to avoid failure in predicting the job performance of candidates? There are many that companies can take advantage of, but two factors would always remain the best bet to make any recruitment process smooth and winning. One is to have standardized interview process, and other is to pay particular attention to behavioral measures. Asking each applicant the same questions in the same fashion yields more relevant data of how each candidate fares.