(1) If members leave, it means they don't belong to the group.
(2) Members who leave are not interested and have the right to go to other groups.
(3) It's everyone's right to leave.
(4) WhatsApp has an open interaction. So everyone has his/her decision to make.
(5) It's impossible to prevent members from leaving.
(6) It's Admin's beliefs that everyone fits in the group, but it's not always true for everyone.
(7) Those who leave help the Admin to know his/her active members.
(8) As Admin, if you added 120 members, it's okay if you remain with 20 active members.
Thanks!