In some countries, when people are arrested, their phone is taken and they would check the telegram to see the messages, especially group messages and members. If the groups has an option to ask a passcode to enter which is checked online (not local passcode), it would be very helpful. In this case, when someone is arrested, the admin can remove the user and when they want to enter the group, they need to enter passcode and be online, which will immediately delete the group since the user is already removed. In this way, no information about the group members and chats will be disclosed.
In some countries, when people are arrested, their phone is taken and they would check the telegram to see the messages, especially group messages and members. If the groups has an option to ask a passcode to enter which is checked online (not local passcode), it would be very helpful. In this case, when someone is arrested, the admin can remove the user and when they want to enter the group, they need to enter passcode and be online, which will immediately delete the group since the user is already removed. In this way, no information about the group members and chats will be disclosed.