Dont understand this equilibrium stuff?

Question

Suppose that a stock has a price that gives it the same expected rate of return as a bank account. Explain why this is not an equilibrium situation. I really dont understand this could someone help me so I can give try and explain it to my class.

Answer 1

I suspect that the bank account is insured, and therefore represents a lower risk investment, so it seems unlikely that one would be willing to invest in a higher risk investment for the same return.