> It is much better to filter out some perfectly good candidates than accidentally hire the wrong candidate. If the companies OP cites were operating under tha

> It is much better to filter out some perfectly good candidates than accidentally hire the wrong candidate. If the companies OP cites were operating under that principle, they should be able to say Hire or No Hire after the last interview. Waiting over 1 month to decide won't make the candidate improve; the only reason to do so is to look for a better candidate, or hire OP if no better candidate is found, but in that case they aren't exactly using the principle above.