I beg to differ. Of course it's not possible for one individual to observe the entire election, but with paper ballots
anyone can understand how the election works:
- voter goes to polling centre
- collect & mark ballot paper
- place ballot paper into locked ballot box
- when polling is over the locked boxes are taken to the counting location and opened
- ballot papers are then counted by hand (machines can be used the speed up the counting, but the option of hand-counting is still there) and the result is announced.
Anyone can understand how this process works, and can observe it in full (except for the actual point when the voter marks their ballot paper, since it's a secret ballot.) And here in the UK, there are observers throughout, not least from the various political parties (each of whom has an interest in ensuring that there isn't any fraud being committed against them) and the media. And if there's a dispute about the result, the counting can be easily verified.
Compare this to using an electronic voting machine:
- voter goes to polling centre
- select preferred candidate on screen and click "vote" (or whatever the UI is)
- ...
- when polling is over, the numbers from the machines are collated and the result is announced.
(I have deliberately left out how the votes are actually counted, as I'm not familiar with the actual systems in use, and (more importantly) this is how it will appear to most voters - as a magic box that takes their selections as an input and spits out a result as the output, with no understanding of how it does that.)
In this system the vast majority of the electorate will have no understanding of how it works, and nobody can observe the actual counting, they are reliant on techies checking the machines and saying "yes, this works properly." And if there is a dispute about whether the machines have counted the votes properly, there is no way to do a recount to verify the result. (I am deliberately ignoring electronic voting machines which produce a paper receipt, because in the event of a dispute the receipts can be counted - the machine is there just providing a faster method of counting.)
The first step to transparency is for people to be able to understand how the system is meant to work, only then can you move on to confirming that the system does work as it is meant to.
Do you see now why paper voting is more transparent that electronic voting?