normaly because every one can post any things but we must be sure that our poste is useful
because we need to post things related to the information of article, to prevent spam.
Because here we are asked to do something that is beneficial to other members so requested not to the origin in answering or asking.
If your comment is not useful for the viewers then your comment will be unapproved and as per regulation of OC points will be deducted.
comments unapproved if they are irrelevant of the topic, Points deducted for performing of spam/scam activity
only related info about the question will be approved.. and the info that is not relevant is considered as not useful and it will be removed.
@M40N3 you are right this deduction is due to the reason that next time the member tries to be careful while commenting.
If our comments do not fulfill the criteria then it is rejected and points deduction is the rule for the unapproved questions.