That line to me is unacceptable. Your(recruiters) job is entirely dealing with people, no coding, no architecture, no design mockups, no capacity analysis or quality testing.

The fact that you cannot even get the people portion right means there is alot of recruiters that should not be in that position. I get that the company itself may be somewhat to blame but not getting back to a candidate should be an offense similar to an engineer pushing untested changes to a production application blindly(meaning it should never happen).