In summary, exceptions and paradoxes are inherent to reactivity theories and models due to the complex interplay of multiple factors. The influence of any single property on chemical reactivity is intertwined with nearly all other properties of the molecules or their environment, though the degree of influence can vary greatly-some properties have a strong influence, while others are essentially negligible. The more specific a statement is, the more likely it is to be wrong, but at the same time it is also likely to be more useful. For example, the general statement "a photocatalyst can degrade during photocatalytic reactions" is completely correct, as it is supported by numerous examples of photocatalyst decomposition. In fact, just one piece of evidence is sufficient to make this statement correct, reducing its value in helping us understand other photocatalytic reactions. In contrast, a more specific statement such as "the presence of a Lewis acid is likely to cause photocatalyst degradation" might be incorrect, but it is far more useful because it offers a clearer direction for investigation. Theories and models strive to find an optimal balance. Therefore, the trade-off between "useful" and "correct" is inevitable, making exceptions and paradoxes prevalent. Identifying new elements and formulating new paradigms can shift this balance, enabling the development of theories and models that are both more correct and more useful.