Look at the scenario. What was Lot's wife doing? She had to be kicked in the butt to get her breathing at the start. She did not want to leave..She was lagging behind when God told them to get out fast. Did she? No. Why not? Do you think God would punish her if she got curious? Curiosity is natural response that God programmed into us. Read deeper.
Actually,
It is Lot who hesitated ((Genesis 19:15-16)), who did not want to flee from the city when he was told to, and Lot who did not want to flee from the valley when told to ((vv. 18-20)), and Lot who did not want the angels to stay in the city square when they expressed their intention ((vv. 2-3)).
All we are told about Lot's wife is that from behind him, she looked, and became an emplacement of salt ((v. 26)).
Nothing is said about her intentions and thoughts, and nothing is said about any other action she took.
Before we can "read deeper" we need to be able to "read."
It is because of Abraham that God preserved Lot ((Genesis 19:29)).
Lot hesitated, and so the ones sent from God took him by the hand and dragged him out of the city.
Lot balked at fleeing to the mountains, and so Zoar, the nearby city he chose was preserved.
Lot went to his sons-in-law, but they though he was kidding ((v. 14)).
His wife and daughters evidently did not think he was kidding.
Why were they saved?
Why did Lot hesitate? Why did he go against the will of the angels so much? Why wasn't Lot turned into a salt emplacement? Was it because after disagreeing with the angels, after arguing with their commands and hesitating and being dragged out of the city not by his own volition, he finally started walking to the nearby city he liked, instead of the mountains he had been commanded to go to? That was enough to keep him from being 'preserved' in salt?
Or was he actually preserved in a different sort of salt?
Of course, weren't these things because of God's compassion, as the scripture says ((vv. 16, 29))? Why did God continue to show compassion to Lot? Did God cease to show compassion to Lot's wife, or is what He did to her also an act of compassion?