I would use the example of asking recipients for self-evaluation as to whether the programs made a difference for them without asking them for supporting documents, or, as another example, having them provide information without providing evidence to back it up.
With the example of the self-evaluations, no information was provided to the recipients to give them a sense of how to answer on the scale. There was a possibility or a risk that information coming back wouldn't be cohesive and coherent.