I understand why people used to like LinkedIn, the promise of finding a job in an easier way by, connecting with peers, colleagues, recruiters, as a social platform to exchange and contribute to communities, etc.
While this might have been true, it's not the case anymore, LinkedIn publishes mainly outdated or fake jobs like any other job boards. It even often just replicates the scam found on other job boards or companies ATS. You therefore find fake ads coming from taleo, jobvite.com, monster.com (sic), and of course from the usual parasites: recruitment firms and HR people who seem to have nothing else to do than posting the same jobs over and over months after months to collect profiles and resumes...
LinkedIn doesn't check nor remove the scams, junks, outdated and fraudulent ads because they probably don't have the resources nor the will to do it but also because they make money with it.
This is why LinkedIn is less and less respected and attractive...