I was an election judge on Nov. 8 (Oak Park precinct 19). My wife heard a rumor that the ballots were discarded after the election. This is not true.
Touch screen ballots: The touch screen mechanism generates a paper ballot, but it does not count your vote. In the next step, the voter inserts this paper ballot into the reader, the ballot is read and counted. The ballot then falls into a compartment, out of sight, below where it is inserted. Think of a mailbox (such as the one on a street corner): when an envelope is inserted, it falls into a bag, out of sight, awaiting collection.
Paper ballot: The same process occurs for a paper ballot that the voter completes with a marker. After being read, it falls into the same compartment.
After the polls close, election judges open this compartment and load the ballots into a large blue bag. (I did this task in my precinct.) The bag is sealed; judges (one from each party) carry the bag to a central location, the Receiving Station. The ballots (that the voters inserted into the reader) are available for recounts (either by machine or by hand).
Every voter can be assured that the ballot inserted into the reader is the final document of your vote. If any dispute arises, the paper ballot that you inserted is the vote that counts. The paper ballot remains available indefinitely.