An example of comments that are not related to the item/place.
A commentary is a place where users can add their opinions on items, places, or decals.
History
The commentary has been added since places were created by players in 2007, with the delay for commenting at the same place starting off at 15 seconds. By later years, the administrators of Roblox decided to limit players from constantly posting comments every second. The limit when posting a comment at the same item/place was from 15 seconds from 2010, to 3,600 seconds (or 1 hour) as of today. This action to extend the delay was done to combat the prevailing spam comments that are continuously appearing on Roblox, which includes those that claim about the ability of a user getting lifetime Builder's Club membership and/or infinite Robux by posting the spam on a certain amount of different items and those that include a potentially harmful link.
Since its creation, users will often post a comment about a different subject rather than the main topic of that commentary. Other players encourage users to do what they ask, such as joining a group, or sending a trade. Some players advertise to try and get attention. However, the majority of the commentary found in Roblox consists of "spam", where players just post comments that is off-topic, and has nothing to do with the subject at all.
As of May 2013, players are required to be verified in order to comment of assets.
When users comment on catalog items (including places, decals, models, etc.), a tiny yellow check mark may appear next to the time the comment was posted. This yellow check mark indicates that the user owns the item.
Spam
Spam is an infamous element in the comments, commonly posted by newer users, group owners/admins, users who want to get the Homestead or Bricksmith Roblox badges by advertising their place at the comments for other users to visit, and sometimes, hackers who post offsite links. However, offsite links are usually reported right away as the hacker can hijack the respective account that went to the link. Some users also attempt to perform an action called "Spam Clean" to get rid of spam by adding a large space in the comment, only resulting in a gap in the comments, thus, it counts as spam. Some users also post parodied spam that is against spam. However, the administrators are trying to protect comments from spam and crack down further on future spam. Unfortunately, some spammers have verified E-mails as of the comment update, thus, the comments section of many items and places continue to contain spam up to this day. Though the moderators are planning to add a spam flag action in the future, thus, many comments, regardless of whether or not they are actual spam comments, will also be flagged as spam by many users when it is implemented.
Anti-Links
Recently, ROBLOX disallowed putting :'s in comments, it now simply displays an error when putting it in. It originally said that "Do not post links!", but this still happens even when the player did not post a link.
A example of a disallowed comment:
Me:Hello!
You can easily see the fact that the comment does not have a link, but there still is a :.