Negotiate a 30-day money back guarantee with the firms who send you candidates. They will only send you proven candidates that have been successful elsewhere.

Negotiate a 30-day money back guarantee with the firms who send you candidates. They will only send you proven candidates that have been successful elsewhere. Don't bother interviewing or maybe have a one person 30 minute culture sanity check. I worked at a household name non-tech company and we negotiated such a deal. It worked great.