Advertisers make great headway tweaking our concerns about what others might think about us. Providing good reasons is important. Providing evidence and reasoning are a strong part of the persuasive process. Appealing to logic may be the hardest of the three sources of influence for the speaker to use. Three types of support material commonly used include examples, statistics, and testimony.
Examples are useful in clarifying, reinforcing, or personalizing ideas.
Ethically, you should help your audience gauge the credibility of your sources, the representativeness of examples and samples, etc. Using examples without other types of support material can come across as weak evidence. Statistics can help. Combing them with examples can be powerful. Using too many statistics can be deadly.