Primarily I think the issue is as simple as the fact that recruitment is fast paced, with a lot of competition for jobs. It is perceived by many companies an unsuccessful candidate has no value to the business, so any time spent giving feedback is wasted time. In my view, a business that provides feedback is more successful and will cut potential recruitment fees for future roles, as often unsuccessful candidates for a particular role can be perfect for another, while maintaining a reputation as a fair and people-centered employer.
For most companies, with written feedback there comes a sense of nervousness. Saying the wrong thing can lead to discrimination claims which is why most companies avoid giving feedback. I think companies have the attitude of, ‘the less I say, the less chance there is of my words getting twisted’. Unfortunately, there are a lot of serial litigants looking for opportunities to pursue discrimination claims relating to interview feedback, so it’s easy to see why some feel it’s better to avoid doing this. But being familiar with the legalities surrounding employment and discrimination can give businesses a solid foundation in recruitment.