Common courtesy and manners….
Sometimes you can receive 100's if not 1,000's of applicants to a job. It is impossible to give them all a personalised and detailed piece of correspondence as to why they are not suitable for a role but should you try?
People will talk about negative experiences a lot more often than they will positive one's - you only need to look at the linked in posts about recruitment consultants to see the truth of that - therefore why do companies often not provide constructive feedback to individuals who have interviewed but been unsuccessful? Why do they not send acknowledgement and regrets to applicants who won't be interviewed?
I admit sometimes it is a volume thing and there just isn't time to do it all but should you not try? Particularly if you are a large company that does a lot of recruitment, otherwise you create a reputation which will hamper recruitment efforts in the future. Even more incredible is companies who don't provide feedback on interviewee's! I represented one individual who cancelled his birthday plans to go to an interview on his birthday, an hour and half each way as a commute and an hour there! He was unsuccessful and all he got was a “no thanks”, no explanation as to why not, no real acknowledgement of the sacrifice he had made to fit into the client plans and therefore presumably his desire and interest in the role – safe to say he is no longer an advocate of that organisation.
It's easy to forget as a recruiter, agency or in house, that what can become a statistic for you is a real person with hopes and dreams and a keen desire to sign up for their perfect job. The least we owe to them for applying is an acknowledgement, the least we owe them for interviewing is an explanation as to why they are not right (and ideally some constructive thoughts on how they can succeed another time). After all it’s just common courtesy and good manners!