Final answer:
The most concise revision of the sentence is 'Voters understand how satisfying casting a ballot can be.'
Step-by-step explanation:
The most concise way to write the sentence without losing important information is: Voters understand how satisfying casting a ballot can be.
This revision conveys the same meaning as the original sentence, but it is more concise and eliminates unnecessary words. It retains the key information about people who have never voted not understanding the satisfaction of voting.