During the 2008 crisis, some banks were doing well financially and had no need to be bailed out.

The main determining factor for whether banks needed bailouts in 2008 hinges upon a commercial banking versus investment banking paradigm.

Commercial banks are more prone towards limiting themselves to smaller profit margins from traditional bank revenue sources. This implies interest earned from loans or generally reliable and stable streams of income. Investment banks have a more untraditional model for generating revenue. They normally have higher potential profit margins on average, but accumulate greater risk as a result. Investment banks also collect a higher proportion of depositor's funds and invest them in whatever ventures they choose, which leaves them in a more leveraged position if investments go bad.

In recent times, within the past 2 decades, most banks shifted away from commercial banking towards investment banking paradigms. And yes there is a high correlation between this trend and the higher proportion of bank failures we've witnessed.

investment banks have taken on greater risk, utilizing a higher percentage of their depositor's funds, with more spectacular negative outcomes. This is the reason so many banks are failing globally, while being unable to pay their customers. Banks are gambling on greater risk / greater reward investments, with the funds of their depositors--those who traditionally believe banks are stable and safe places to store money.