The listener assesses the information she's gathered from the speaker both qualitatively and quantitatively.
Evaluating allows the listener to form an opinion of what she's heard.
Evaluating is important for a listener in terms of how what she's heard will affect her own ideas, decisions, actions, and/or beliefs.
The Evaluating Stage
Once we understand what we hear, we can focus in on the relevant information.
This stage of the listening process is the one during which the listener assesses the information she's received, both qualitatively and quantitatively. Evaluating allows the listener to form an opinion of what she's heard and, if necessary, to begin developing a response.
During the evaluating stage, the listener determines whether or not the information she's heard and understood from the speaker is well constructed or disorganized, biased or unbiased, true or false, significant or insignificant. She also ascertains how and why the speaker has come up with and conveyed the message that she's delivered. This may involve considerations of a speaker's personal or professional motivations and goals. For example, a listener may determine that a co-worker's vehement condemnation of another for jamming the copier is factually correct, but may also understand that the co-worker's child is sick and that may be putting him on edge. A voter who listens to and understands the points made in a political candidate's stump speech can decide whether or not those points were convincing enough to earn her vote.
The evaluating stage occurs most effectively once the listener fully understands what the speaker is trying to say. While we can, and sometimes do, form opinions of information and ideas that we don't fully understand--or even that we misunderstand--doing so is not often ideal in the long run. Having a clear understanding of a speaker's message allows a listener to evaluate that message without getting bogged down in ambiguities or spending unnecessary time and energy addressing points that may be tangential or otherwise nonessential.
This stage of critical analysis is important for a listener in terms of how what she's heard will affect her own ideas, decisions, actions, and/or beliefs.
Source: Source: Boundless. “The Evaluating Stage.” Public Speaking. Boundless, 26 May. 2016. Retrieved 27 Oct. 2016 from https://www.boundless.com/users/483275/textbooks/public-speaking-0f5d9d6f-0c83-4aba-883c-58ac2df122eb/unit-1-342/develop-critical-listening-skills-articulate-the-speaking-listening-process-apply-critical-listening-to-analyze-the-strengths-and-weaknesses-of-speeches-evaluating-both-content-and-delivery-evaluate-your-own-speeches-and-provide-constructive-criticism-540/the-evaluating-stage-547-476/
to determine, estimate or judge the value of; to evaluate
the stage of the listening process during which the listener critically assesses the information she's received from the speaker
merely touching, referring to a tangent, only indirectly related