I have rarely gotten feedback from interviews, but when I do it is always interesting.
You should always thank people who give you feedback. That is a nice thing to do and can be helpful in some situations. Most of the time it isn’t helpful.
For example, I once had an interview that during the interview I didn’t feel that I had enough knowledge to do the job. What the recruiter said and what the reality was, was very different. I did my best and figured that I would never hear back from them again.
However the next day the recruiter called and said they liked me but unfortunately I was too security focused. I thanked him and said I am not a silver bullet and that was fine and good luck finding the right person.
Now what can you do with this feedback? Most companies are securing their environments that I have worked with, and that has been a large part of what I have done. I didn’t feel that I wasted time with the interview. Even an interview for a job that I can’t do gives me important insight into what companies are doing and what I should study and work towards.
Just to be transparent I have also received feedback that I was too focused on documentation or customer service. It is interesting, because every recruiter that provided feedback when they didn’t choose me, choose me to interview. Often it feels that you are helping to educate recruiters on technology and what it means to be a successful candidate in that role.
Should I turn down interviews and grill recruiters more before I have interviews? The sad fact is that many recruiters don’t understand beyond a job description, and when the job description isn’t detailed you don’t know. I could be turning down a great opportunity. I would rather be told no I don’t qualify than to miss a good opportunity.
Will this feedback change my future behavior? No. Feedback rarely changes my behavior. Not because I know it all, but because the needs of a company are different. If I focus less on security on my next interview, then they may feel I haven’t had enough experience to do what they need me to do. I am interested in security both personally and professionally, so I want to continue to use that skill. Its ok if someone rejects you for a strength. There are plenty of companies who need that strength and skill.
This isn’t to brag, but rather to remind you that feedback is rarely useful and your own knowledge of self is the most important to having a job and being content in life.