You have run a Smart Campaign with a single flow step, Change Data Value, and you do not see the entire campaign membership in the Results Tab.




 If the Flow step is changing an attribute to a given value ("example value"), but a lead record that qualified for the campaign already has that value ("example value") in the field, there will be no change and the record will not display in the Results tab.

Since the record already has the value, Marketo will not write another change on the activity log and so the record will not show in the Results Tab.