Spirit’s rejection was a gift to JetBlue which was already offering to overpay for Spirit. The “winner’s curse” was in effect, Since the market knows what Spirit is worth, in order to ‘win’ JetBlue was having to overpay. And indeed, Spirit is worth less to JetBlue than it is to Frontier.
JetBlue’s revised offer, unfortunately for their shareholders, was the same amount of money while extracting less value from the deal.