Cash flow yield default, limitation, another, whether

bcp901

In one vignette Schwer says

Cash flow yield does not consider credit risk assumption. (In the same choice one answer was one of the limitations was default risk was constant over the life). This is ok.


In another vignette, it says default risk was constant is not a limitation.


Can any one clarify whether credit risk and default risks are limitations or not. What are the limitations of cash flow yield.

thanks