Optical machines do not have chads. Those are "punch card" machines. The low toner comment doesn't make any sense. The ballots are printed BEFORE the election. If you get a ballot that you can't read, you can return it to the pollster, they will mark the ballot as "unusable" and give you another. I know this because I've done this when I accidentally filled in the wrong circle. It's SOP.

Incompletely filled-in bubbles is a real problem, true, but in my experience I've never seen this.