Xia Fei's reasoning was very easy to follow. There was no way a drone cobbled together at the last minute could perform too well, so he invested everything toward offense, like a dead man's final struggle. When faced against a battle that there was no way of achieving victory, a true warrior would never choose to flee but use what's left of their life to execute one final attack.
It would of course be a cause for celebration if they emerged victorious, but if the attack was met with failure, there would not be any regrets since they had already done their best.