Say for example 1000 people apply for 1 graduate position on a companies website. I find it unlikely that they are going to read everyone's resumes or am I wrong? What steps do they do to filter out the applicants to finally get the 1 successful applicant?
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Generally they have automated screening that removes anyone not meeting a particular set of criteria. Be use to use the key words in the job ad and make sure to exactly follow any directions they give for submission as people who don;t follow direction are generally immediately filtered out.
The resumes left after that are often reviewed by an HR person who further screens out people considered less qualified, then those resumes left go to the hiring manager(s) who determines who to interview.
And for the record, yes I did review well over a 1000 resumes one time when we were hiring more than 100 new people. We even interviewed several hundred. So yes the resume may get reviewed even when there are a lot of them or it might be mostly handled by an automated system.