Rejection rate has been discussed many times. It is not the most important metric since it's just an observation. You can't start with a desired rejection rate

Rejection rate has been discussed many times. It is not the most important metric since it's just an observation. You can't start with a desired rejection rate and come up with a good interview process. What you can do is know what kind of person you want to reject or select for, design a process to do that, and then adjust other factors (listed compensation, recruiter talent, marketing site, etc.) so that you have enough candidates to which you want to extend offers. Few companies are actually in a position, given their knowledge, stability of their industry, and marginal quality of hiring success, to succeed at deliberately loosening or tightening their interview process to arrive at just the right number of final candidates.