Creating overrides using default options versus using a group?

Question

What is the difference between creating a group so it can be chosen for an monitor or rule override versus making an override such as for a class of ,.... I am referring to those four choices like class, object of class,...that are available.
A group is just used to select computers. What is the difference between choosing a class of something versus creating a dynamic group. I cannot really think of a reason to use one over the other?

Answer 1

Classes:
In Operations Manager, a class is a definition of an item that can be discovered and managed. A class can represent a computer, a database, a service, a disk, an application, or any other kind of object that requires monitoring.
Every SCOM object is an instance of class. This means that you cannot

Groups:
In Operations Manager, a group is a logical set of objects that can be used to define the scope of overrides, views, user roles, and notifications.

A monitor or rule is applied to a specific class. To change the value for a parameter of a rule or monitor, you create an override. You have the following options for applying your override:

For detail, pls. refer Using classes and groups for overrides
https://learn.microsoft.com/en-us/system-center/scom/manage-mp-overview-override-targets?view=sc-om-2019

Roger