The article discusses how high expectations of house prices can lead to more risky loans being given out, which can in turn contribute to a housing bubble. The researchers suggest that when lenders believe house prices will keep rising, they are more likely to give loans to people with poor credit histories. This can create a cycle where risky lending drives up house prices, leading to a bubble. The study uses a mix of theory and real-world data to show a connection between price expectations and the amount of risky loans being issued.