Fundamentally, this probably would be the case where the person does not use the proper equipment or system and software, so a third party could get in between, and the data in transit could be altered or changed, etc. That's how I can see it from the human perspective: an error to allow a vote to be altered and changed. It also makes a good understanding from the perspective of a person to be educated about encryption and how, from her end, data can be encrypted and sent to the other end so that the data in transit will not be altered, changed or grabbed. That's how I see it from the human perspective: errors that could be made.
Evidence of meeting #22 for Procedure and House Affairs in the 43rd Parliament, 1st session. (The original version is on Parliament’s site, as are the minutes.) The winning word was vote.
A recording is available from Parliament.