For a bank, book value is close to the economic reality because the assets are financial and marked in some fashion. For a manufacturer it is a historical cost artefact, and for a software company it is close to irrelevant.
The multiple only makes sense alongside return-on-equity. A bank earning 15% on equity should trade well above book; one earning 6% should trade below, and the relationship is roughly linear.
Example: Meridian Savings Bank has $840M of tangible book value and a $1.1B market cap, 1.3 times, consistent with its 11% return on tangible equity.
Related: tangible-book-value, return-on-equity, tier-1-capital, shareholders-equity, valuation-multiple