There are a lot of people who use video relay services if they find it very difficult to hear, or they are completely deaf. It helps quite a bit in allowing people to communicate with so many different people, and technology has really increased how it works as well.
There used to be a time where it was very difficult to communicate with others all around the world if a person did not hear correctly. Using a standard telephone would not work, so doing some type of video chat was only a way to do a full communication. Online options now allow for this to happen, and it is much cheaper than ever before.
All a person has to do is make contact with someone else and go from there. Video is so strong that it is very easy to see exactly what the other person is signing.