According to statistics, 75% of recruiters and hiring professionals use an applicant tracking system. This shows how its importance is growing with the changing times.
Many companies receive 500+ job applications per week. A human can’t read every single curriculum vitae. Hence, an ATS automatically rejects many curriculum vitae. Only the top curriculum vitae identified by the ATS are read by a human.

Unfortunately, the answer to this question is that candidates are rejected very often.
These are the two main reasons why qualified applicants may be rejected:
Improper document format: Contrary to popular opinion, .pdf files are often difficult for applicant tracking systems to process.
Not using the right keywords: An applicant may not match the keywords in the curriculum vitae with the job description. Unfortunately, this can lower an applicant’s score after being processed by the ATS. Make sure that you tailor your CV according to every single job posting. You may apply to 1000’s of companies, but only a personalized CV will be noticed by a recruiter.