People move to different states for a wide variety of reasons.
Throughout history, workers have followed employment opportunities. A college graduate studying finance in the Midwest could have more success finding a job in a financial hub such as Manhattan, New York, or Chicago, Illinois. A recently minted computer programmer from Vermont may have more success in San Jose, California, or upcoming tech cities such as Raleigh, North Carolina, Austin, Texas, or Denver, Colorado. Or generally, if unemployment is high in a certain region, skilled labor force participants may seek greener pastures elsewhere in the county.
Businesses have motivations to settle in more tax-friendly states. A business headquartered in Massachusetts looking to expand to multiple locations may choose Nevada over Arizona because Nevada doesn't have state income tax while Arizona does.
Lifestyle & Demographic Shifts
A retired couple in Pennsylvania may decide to relocate to Florida because of Florida’s favorable climate and no state income tax obligation on their monthly pension payments. It's no mystery why so many residents in the Northeast flock to Florida during their golden years.
A dollar is not equal in every state. A house in Atlanta, Georgia, will be cheaper on average than a similar home in Seattle, Washington. A gallon of gasoline in Honolulu, Hawaii, will be more costly than a gallon in Nashville, Tennessee. Cost-of-living information is accessible to anyone with an internet connection. Affordability is arguably more prevalent than ever before as more employers are open to 100% remote work due to the Covid-19 pandemic.
People who were once geographically tied to jobs have more flexibility to cherry-pick a state of residence based on where their salary will go the furthest.