Why do hotels require minors to write their names, phone numbers and ID cards?

Because according to Article 6 of the Measures for the Administration of Public Security in Hotel Industry, hotels must register for receiving passengers. In order to ensure the safety of minors and the safety of check-in, it is clearly required that citizens must provide their valid identity cards when staying in hotels, so citizens must provide their identity card registration information when staying in hotels.

It may also be that minors cannot pass the verification on the system, and the hotel needs minors to write down their names and telephone ID cards.