This is just plain unethical on the part of the company. It sends the wrong message: hop from job to job and you are the best. I don't believe that is true. I have seen people hired externally who initially make a good impression and some progress. Then "bam" they discover that after the "honeymoon" period has worn off, they don't have the "magic" they had by being new. Off to another gig they go. Then companies complain about engagement. Its obvious to me that this is part of the issue: employees who choose to stay are viewed as having less potential than people who decide to job hop. It becomes a self-perpetuating with consistent turnover and looking for someone "new" to come in and solve problems that would best be solved by internal cultural informants.