Impicit measures are created automatically when we drag a column of values into a visual. Explicit measures are created manually and define how the column should be summarized.

What are the advantages of using explicit measures in pivot tables? $($Select $4)$

You have greater control over the outcome, which is even more important when handing over the model to another user.

Because implicit functions don't get saved when you remove them from a visual.

Because it's nice to have a complete list of measures.

To ensure that you always know what aggregation is being done.

Because we can define the formatting of explicit measures, and maintain consistent presentation when the measures are used in different visuals.