Those 'one specific person' ads are usually there to comply with an internal requirement or external regulation/law, so they wouldn't be able to say that it was filled, because that would be an admission that the whole process was a sham.
So, I convert my resume into the job description that would be posted. Thinking it will get 100% hit rate. Lo and behold, someone else took that job description and basically converted it into their resume. And got a higher ATS score!