Why was the firefly and ladybug state insects?

You're asking about the firefly and ladybug as state insects, but they are not the state insects of any US state.

* The firefly (lightning bug) is not the state insect of any state.

* The ladybug (lady beetle) is the state insect of only one state: Ohio.

Perhaps you are thinking of other insects, such as the honeybee which is the state insect of many states.

If you have any other questions about specific insects or their state designations, feel free to ask! 😊