Why Daenarys was beyond madness

1. Destroying a city to win the war is collateral damage but make sure to kill everyone just to be sure everyone hates you now;
2. Just to be really sure everyone hates you, agree the day before to spare people if they surrender and then Don't do it;
3. If you made up your mind and want to destroy everything, take a break before you do just to be sure everyone knows you did it on purpose;