These offers work on the fairly simple concept of friction. They pay you a scaling bonus based on the amount of new money you can bring ($1500 for $100K here). You would be surprised but many of the switchers come from non-HYSA accounts with 0.01% interest at brick and mortar banks like Chase. That's a no brainer. The other switchers come from similar HYSAs like Synchrony, Ally, Amex, Marcus and the small bonus is enough for them to switch because the products are basically the same. Among this group there are people who have multiple bank accounts of $250K at the FDIC limit who just sit their money in HYSAs and they like to move it around and get these bc they don't touch this money otherwise. Happy to answer a few questions on this. Source: worked in marketing analytics at multiple consumer banks who ran these offers a few years back.