In France we don't actually write anything. When we enter the room we're given one paper per candidate with the name and logo printed clearly. Once in the voting booth we put one or none in the enveloppe. That's it. Problem solved.
If the envelope contains more than one vote, but all are the same, it counts as one. If the envelop contains more than one vote but they are different it does not count.
In the voting school there are randomly chosen citizens and party representatives that identify the voters, all adults must have a national ID, and count the votes.
It works, and it will need a massive amount of people to change a significant amount of votes.
I don't know about other countries, but here in New Zealand elections are monitored by the Electoral Commission who employ people to watch every step of the process. In addition every political party is entitled to send scrutineers to polling places and the count. The boxes are shown to the scrutineers who verify it to be empty, then sealed. The boxes are never taken out of sight. Every step of the process is under multiple eyes.
This seems to work well. It's possible to double vote by visiting multiple stations but in practice this is rare. It does happen but the electoral commission do analysis on the votes to ensure it didn't affect the outcome. Those responsible are prosecuted.
The way to ensure the ballot is secure is to have a fully publicly verifiable end-to-end process. You should be able to watch the ballot box from the moment you put your vote in, all the way to the count.
And if you think about it, you actually don't want to check that _your_ vote has been counted.
*reasonable exceptions exists