Although you see the villain making his way out through a side exit, you also see that he could likely kill you in your current state. Although you can usually save yourself while the bad guys are stuck on a monologue, it's not worth betting your life on. With his weapon and army disabled, you slip back home to recover.
Unbeknownst to you, your foe planned on this. Did you think he was some sort of amateur with no backup plan? With his primary plan ruined, the fiend deonates bombs around the city, costing hundreds of lives and crippling commerce. You, too, feel crippled, as the failure to stop your enemy hangs over you like a dense cloud. The feeling lingers as you wake.