As of the end of $2022,$ Silicon Valley Bank $($SVB$)$ had a PCA designation of Well Capitalized; determined by all of the PCA financial ratios. SVB reported $$14\mathrm{.}5$ billion of common equity capital on its December $2022$ Call Report balance sheet. This "Well Capitalized" bank was taken over by the FDIC on March $10,$ as the bank could not handle a sudden outflow of $$46$ billion of deposits, and thus the bank failed. In reality the balance sheet was quite fragile. No healthy bank is ever going to have a run on the bank and thus fail. What reasons $($there$\text{'}$s more than one$)$ were behind this bank's fragility, and thus caused the bank to be a sitting duck for a loss of confidence.