A good example of a useful macro is one for drawings Titleblocks:
Without a macro, you could add/change the desired drawing border, and then add Text to fill in the titleblock areas. Of course, you want to carefully type the correct PN, title, revison, EC number, scale, sheets, toleranaces, etc., making sure everything is in the correct view, correct font, size, layer, and position, and then verify that what you typed matches the information that is in the PDM system for that particular drawing. Of course, if you have to change the drawing size, you probably have to modify some of this data accordingly. How many drawings do you work on every day?
A macro could be written to automate most of this work for you. Some data still needs to be entered (maybe on a simple form), but lots of data could be pulled from the drawing properties or directly from the PDM system. No typos, and everything in the correct position, size, etc. More time to spend on design. Less time required to check the drawing.