At a recent venture capital conference in Phoenix, a group of chief executive officers challenged Roger V. Smith, president and CEO of Silicon Valley Bank, in San Jose, Calif., to explain why bankers, as a breed, were so averse to risk, while venture capitalists seemed to accept it as a fact of life. "We're not like venture capitalists," replied Smith. "We're like Hertz Rent-a-Car. When they rent you a car, they charge you for usage, and they expect to get the car back. When we give you a loan, we charge interest, and expect to get our money back."