Traditionally, recruiters use large job boards, niche job boards, as well as social and business networking to locate these individuals. The immediate goal of internet recruiting is to find individuals that a recruiter or company can present to hiring managers for the purpose of employment. Quite often, Internet recruiters have very short-term goals when it comes to recruiting online. The general catalyst that sparks this process is when a new job requisite comes in (called a REQ). The recruiter scans his or her database to see if anyone's resumes match the requirements. If not, they proceed to search on the Internet.
The challenge arises when recruiters contact passive candidates willy-nilly. If a person is not currently seeking for a job, they generally have no interest in learning about new positions. Excessive contacts of this nature could lead to complaints of spam. A far more logical way to approach internet recruiting is for recruiters to view themselves as an authority site and answer the WIIFM question that all individuals have: "What's in it for me to act upon your email"?
If a recruiter also offers resources such as career help, salary information, how to manage job stress, and the like, they break out of the stereotypical headhunter mode and enter into the "valued resource" mode to the individuals they contact.
Reference: Wikipedia
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