The point of elections is that people en mass need to trust them and be certain that their fellow citizens did in fact vote as the numbers claim that they did.
Paper (in person and see through urns preferably) is a very accessible way to do that and allows even nontechnical people to witness and verify it with their own eyes.
In most countries with free elections, regular people can supervise their local elections (within reason and if they are able to behave themselves).
With electronic machines you have all the problems you have with paper (e.g. political shenanigans and politicians doubting the results without proof etc) and in addition there suddenly is a totally oblique process on the local level (seeing is believing and no one can see inside a computer memory)
What's the benefit? What do we gain? If counting paper takes too long get more people to do the counting.