Some possible advantages of voting machines:
- They can provide different accessibility assistance than pen and paper, allowing people to vote on their own. Multi-language support should be easy.
- They can provide UI improvements over paper. Consider situations where the voter needs to select up to 3 candidates out of a list of 12. Or a long ballot with lots of distinct questions.
- Hopefully less lead time for updates to the ballot if someone drops out of the race, is replaced, etc.
The past few times I've voted (Canada) it's been pencil on paper, stuck into a machine that confirmed it could read the ballot, then I left. When it's been a longer ballot for municipal election it's actually felt like a bit of a test. We are voting for: city councillor, mayor, regional representatives, multiple school board trustees from one of two different school boards (but not both).