If it is supposed to be the “Gateway to the West”, Missouri is probably seen as the gateway to other states, since more than half his population leave, with 51% of people moving out. For 63% of them, the reason they leave is to get a job, and even having Budweiser in St. Louis isn’t a good enough reason for them to stay in Missouri.
Unfortunately, Kansas City has been losing 1.9% of its manufacturing jobs because of many factories closing, and the city’s Harley-Davidson plant also shut down in 2019, causing 800 people to lose their jobs. But the weather is also a good reason for people to leave, humid summers and very cold winters meaning it goes rapidly from one extreme to the other.