Lever Voting Machines (or LVMs), which are still in use only in New York, are about as old as voting technology gets here in the United States. (Learn all about them — and every other voting machine used in the U.S. — with our in-depth map of voting tech.)
Inside every machine, votes are counted mechanically on odometers — just like the ones that count the miles traveled in older vehicles. Before voting begins on Election Day, these odometers are set to 0-0-0. At the end of the day, poll workers check out the counts. The most frightening thing for them to see is a meter that says 0-9-9.
If an odometer reads 0-9-9 (as the image above has been altered to show, for example), it very rarely means that 99 votes were cast for a specific candidate, but that the pins used to advance the reading to 1-0-0 snapped and stopped the count at 99. Since two wheels are being spun to advance the hundredths counter, more force is applied on the aging or plastic pins. It's the most likely failure to occur in LVMs.
Of course, this means any votes over 99 are lost forever. Not cool, democracy.