In conditional formatting, what could be a reason for a rule not applying?

In conditional formatting, a rule may not apply due to conflicts within the conditions set or if the data type does not align with the rule's requirements. This can happen, for example, if you have a rule that applies formatting based on numeric values but the data in the cell is formatted as text. If the conditional formatting rule is designed to check for values like "greater than 10," and the cell actually contains the text "10" (instead of the number 10), the rule will not apply because it cannot evaluate the text string as a number. Similarly, if there are multiple rules set that apply to the same range of cells but conditionally contradict each other, Excel may disregard one rule in favor of another, leading to the formatting not being applied as expected. These factors ensure that the conditional formatting operates under specific logic and data type compatibility.