As a retired engineer, I do know that things fail. There is a B10 life on all components. This means that 10% of the components will fail below their expected useful life and that varies by manufacture of said component. You might have gotten some of these components, there is no way to know unless a failure analysis has been done of the failed bearings.
Just follow your maintenance schedule for your given vehicle and check the components when required. I know that my vehicle maintenance schedule calls for the wheel bearings to be inspected every 30K miles.
2016 34RL CC; 2008 Ram Mega Cab 2500HD, 6.7L, 68RFE 6 speed, 4X4, Smarty S67