The author's faulty reasoning invites criticism by falsely comparing the eating of salad to student success.
The author claims that every successful student they know eats salad for lunch. However, this is not enough evidence to support the conclusion that eating salad makes you a successful student. There could be other factors that contribute to these students' success, such as their intelligence, hard work, or support system. Additionally, the author does not consider the possibility that there are successful students who do not eat salad for lunch.
The author's argument is also weakened by the fact that they do not consider the food choices of successful students at other meals. For example, it is possible that some successful students eat salad for lunch but eat unhealthy foods for dinner. This suggests that eating salad is not the only factor that contributes to student success.
Overall, the author's argument is based on faulty reasoning and is therefore not convincing.