Question

why was letter writing done more carefully in the past? ​

Answer 1

It was harder. The more difficult it is to correct errors the more careful people are about not making them. It was more expensive (both in terms of time and materials). The more expensive something is, the more we tend to take care of it. It was more important, today we have so many forms of communication that we can be more casual and even careless. When letters were the principle form of communication across distances we treated it with greater significance.