Everytime I was a pole watcher, I was just a few feet away.
Every count and re-count has been consistent. I have reported and dealt with suspected election fraud. Does it happen, yes. Have I have seen it be enough to affect an election outcome. No.
Look at Georgia. The hand recount of all the original paper ballots was within .1% of original count. If a change made to machine's ballot tabulation programming was done, the exact same change would have to be made to EVERY PAPER BALLOT. That is pretty much impossible.
You can have confidence it was a fair election, even if it wasn't the outcome wanted.