How is that different from paper polls? Once you deposit the ballot you don't keep any record of your vote. One of the reasons for the vote being secret and no

How is that different from paper polls? Once you deposit the ballot you don't keep any record of your vote. One of the reasons for the vote being secret and not leaving the ballot is to avoid people being coerced to vote for any particular candidate. In Brazil we have the concept of electoral corrals. This is a known and wide practice, although it was much worse in the past. Electoral courts and processes have been fighting this since the early days of Brazilian democracy. In a nutshell, this is when someone who holds a certain amount of power over many individuals (an employer, a farmer, a community leader, a church pastor, etc) exercises this power in order to coerce people into voting for their favoured candidate even if it goes against the individual's best interests and preference. They would make people prove that they voted for candidate A, or get fired, expelled from the community, perhaps even fear for their or their family's lives. These practices still happen and have increased massively this year compared to previous elections, but they're still lower than they used to be. If people left the ballot with proof of whom they voted for, it would be much easier to coerce them. With a secret vote being enforced the way it is, individuals still have the choice to agree with their superiors but cast whatever vote they want. It's not perfect. Like I mentioned, the problem still exists, but it's reduced. Like other commenters have already said though, the ballots are auditable (and audited). I would rather our systems and processes keep improving rather than going back to worse ways just because what we have now is not perfect.