Customers who see their main bank as a customer advocate that does what's best for them, and not just what's best for its profits, are more likely to consider it for future financial purchases. On average, only 27% of Western European adults believe that their bank acts in their best interest. There are differences between European banks, however. What separates the winners and losers? The top-rated banks keep things simple, operate transparently, build trust, and treat their customers benevolently.