Why is missing data filled in DataFrame with some value ?

The dropna() method in pandas can be used to remove rows or columns with missing values from a DataFrame. However, this can also lead to a loss of non-null data, which may not be desirable for data analysis. To avoid losing non-null data, we can use the fillna() method to fill missing values with a specified value. This can help to ensure that the dataset is complete and can be used for data analysis.