Why does a speaker have a responsibility to evaluate the sources used in a presentation? What could happen if supporting material is not evaluated?

This question is incomplete, but I will answer it anyway in a way that you can understand.

Explanation:

 A speaker has the responsibility to evaluate the sources he is using for his speech given that he is providing information, and such information cannot be wrong. Especially if the speaker is using this data to support his ideas, emphasize or clarify them, and providing false data or not checking the sources of his speech can end in his speech being ruined, since he will not be able to convince his audience or he will lose his credibility.

each poet admires poetry

they each admire poetry because they could just use an expression or verbally just say you but they both write in in poetry which shows they know how to write in poetry.

same test same problem