When should you use a CAD block instead of a group?

[indiancad]

In large 2D drawings, similar objects such as symbols, equipment layouts, and standard details are often repeated several times.

Using blocks makes it possible to update all instances from a single definition, while groups allow objects to be selected and handled together without creating a reusable block definition.

Choosing the wrong approach can make later editing and drawing maintenance more difficult.

When managing repeated geometry in production drawings, do you prefer blocks or groups? What factors influence your choice?