There are many works during the competition. After installation, it occupies a large area and it is very troublesome to open them. After all, most of the works stop at the preliminary competition, and it takes time and effort to mount them. Maybe people just open them and throw them away. Therefore, in the preliminary competition, the organizers generally ask not to mount. Generally speaking, they only need to write the works on some paper to send them out, and there is no need for any mounting process, so the efficiency is high, and the preliminary competition generally does not reject the manuscripts.