[throwaway2333]

Sales funnels.

You can only nudge conversions to each successive "step" so much. Once you've reached diminishing returns, the only thing left to do is get more leads into the funnel -- grind the process out/pick up the phone and dial.

Feast or famine jobs also don't lend themselves well to "long-term thinking." If something is working, don't break it, just keep on going and make that paper. If something isn't working, you don't have the time/soundness of mind to figure it out, just keep on going (or else you won't be able to pay your bills).

Jobs are a commodity and the only selling point is price/pay -- making it one of the worst things to "sell" (the "best"/easiest things to sell are the antithesis of this).