Many electronic voting machine does both the "voting selection" and "vote casting".
Securing voting machines is hard.
Thus we really should be separating the function of "voting" and "casting" to two separate mechanism, joined only by a carefully scrutinized API/interface (e.g. inputting your preference via NFC/QR/Smartcard ).
By keeping the mechanism of user vote selection outside of the actual vote casting mechanism itself. It would give the opportunity to do some pretty funky stuff, like a vote suggestion app. To which you can download a 3rd party app, that may ask you a bunch of questions before giving you a recommended voting setting. If you don't trust that app, you can download a different one.-- mofosyne, Aug 23 2015random, halfbakery