when importing a Text file, why is it important to move through each step of the Text Import Wizard?

The last step provides the option to select the column data format so you can select the format of Text for fields that have leading zeros.

It is the only way to allow the Text Import Wizard to refresh the import with new data.

The last step provides the option create calculated columns.

The last step gives you the option to change the column headings (field names).