Ranking applicants as 'Thumbs Down' (aka unsuccessful) has 3 mains benefits:
1. Helping you remove inappropriate applicants so you can focus on applicants who may be more suitable.
2. You may also be offered the option to send the applicant an unsuccessful email which they really appreciate. (You will need to contact applicants directly if you have selected the [Interview] or [Hired] button as our generic email is not appropriate).
3. If the applicant has registered a job seeker account they will also be able to see they have been unsuccessful. However your details are kept confidential so if you change your mind the risk to your reputation is low