Her mass murder didn't make any logical sense!
Was she supposed to ignore cersei's army which cersei had specifically said she had strategically intermingled with the townsfolk to slow dany down?
Would it help if she'd spent most of her life with ther dothraki, who lay waste to villages, and the one time she stopped them it ended with the loss of her husband, her son and her ability to ever bear children again?
Would it help if she were a targaryen, known for taking westeros by burning cities to the ground with their dragons?
Would it help is king Robert had tried to kill her because the thought of a targaryen with a dragon and a dothraki hoarde coming to kings landing terrified him?
Would it help if she'd met with her advisors in season 7 and tyrion had to advise her not to go destroy kings landing?
What about if she'd followed the advice, saying she didn't want to be queen of the ashes, but all of their alternative plans had failed miserably?
Was she supposed to have her dragons burn people to send a message like she did in mereen with one of the masters?
Was she supposed to do it again to send a message like she did with the tarleys?
Was she supposed to act remorseless about killing people with her dragons like she did when she calmly told samwise that she'd killed his father and brother?
Was she supposed to kill countless people like she did with the ships in slavers bay, the money train, the army of the dead, and the iron fleet?
Maybe if jorah had just died in her arms and then her dragon got shot down in front of her and then miss sandy got decapitated in front of her?
Maybe if varys openly betrayed her, and from her perspective tyrion appeared to have betrayed her as well?
Maybe if jon's claim to the throne was being made public hours before she finally completed her life long goal of taking kings landing?
Maybe if jon rejected her and the only path left to the throne was to rule by fear?
If that's not enough buildup, what would it take to make mass murder seem logical to you?