2, this thing depends entirely on your own hobbies. As long as some people like it, some people don't. There are many people who don't write. Write something if you like it, and don't write if you don't like it. It doesn't matter. There is no clear requirement for this thing.
3, because they are very casual, just live a simple life casually.
Qq and WeChat signature are extended functions of Tencent QQ and WeChat chat software, which was launched by Tencent in 2005. There is a column of personalized signature in your personal profile. You can set your own unique personalized signature according to your hobbies and mood. When a friend chats with you, there is a set personality signature on the right side of the chat window avatar.