'Recommend' is a way for people in your company and others to show their support for the job posting you have published, which helps to reach more people to see your postings.
People who click on 'Recommend' also have the option to share job postings on their connected social media accounts. Also the more 'Recommend' is clicked, the better chance the job postings be displayed on Wantedly top page.
Share it with your own comments might help to capture more attention.
*In order to share on facebook, make sure your Wantedly account is connected with your Facebook account. Go to privacy setting to make changes.