There have been multiple cases of village theft in the past due to mayors not setting their permissions correctly or giving them to the wrong people which lead to many items being stolen. Luckily we could always retreat the items and ban the thieves. But it takes a lot of time and effort from the staff team to do so and all this could be easily avoided by just setting your perms correctly.
Be careful of who you trust! DO NOT give villagers/alliance members full permissions if you do NOT know them personally or 100% trust them.