> the income difference someone makes by being placed in the ideal job sooner. I don't know how you can tell what I'm factoring in or not, since I deliberately

> the income difference someone makes by being placed in the ideal job sooner. I don't know how you can tell what I'm factoring in or not, since I deliberately avoided this calculation. It can benefit either employees or employers, depending on elasticity / market power. In other words: you're not factoring how much faster expensive senior employees can be replaced with recent grads ;). That said, there is also a cost to sloppy, spammy recruiting, illustrated in the other responses: it can end up increasing stickiness if enough people start ignoring all recruiting communication because it is all spam. That makes it even harder/more expensive to recruit, and grows the market for recruiters. There are some nasty incentive structures in there.