People in teams don't want to be bothered with messages that don't pertain to them. It makes concentrating on other important tasks difficult. But if you make a comment and don't mention anyone in it....well, it's like when a tree that falls in the woods and nobody is around to hear it. So, when you add a comment to a conversation in Teams be sure to @mention the team or individuals involved so that they will see it. Just type the "@" and start typing letters that start a name or a Team. Auto complete will pull up a list and you can click on the people you want to mention. (see below)