I've changed jobs ten times since 1992. As it works out, exactly half of them I was recruited into by an internal reference and the other half I found on a job board like Monster or LinkedIn. By far, the two best were relatively large organizations that I applied to cold, and the two absolute worst were actually the ones I was most actively recruited into by former co-workers. I suspect that the problem in both of the latter cases was that they worked so hard to bring me in that they ended up overselling me - I'm good, but I'm also a human who has two kids to look after. On the other hand, if I'm "just" the best candidate from the pile of resumes, expectations seem to be reasonable.