Wrong paper format: If the paper format is set incorrectly, the paper detection system may not correctly identify and process the paper content.

Thesis library is not covered: some papers may not be covered by the duplicate checking system, which may be because the database used by the system is small or the publishing institution of the paper has not submitted the papers to the duplicate checking system.

Content of the paper: If the content of the paper is too simple or the quality is not high, it may be ignored by the duplicate checking system or cannot be accurately compared.

Problems with the duplicate checking system: Sometimes the duplicate checking system may fail or make mistakes, which makes it impossible to compare and identify the contents of the paper correctly.

Different duplicate checking systems may have different implementations. The first draft can be made by paper Free and papertime, and the final draft can be made by the school, which needs to be analyzed and processed according to the specific situation.