I'm going to digress from the economics a tad and focus on the ethics of this. I feel like companies should be on the hook for this. You should invest in capital (including human labor) based on your confidence in its expected return. Companies should not be able to hire a myriad of workers for funzies and not have to meaningfully consider if that person will be necessary in 6 months. If it is a legitimate business venture, then the cost of potential severance for new hires should be folded into the economics of the decision to pursue that venture. Larger severance pay/worker protections encourage employers to not utilize exploitative hiring practices.