I personally have to have some connection to a tartan. For a family tartan I want some sort of ancestral link, although it may be back several generations. For a military tartan, I will wear the US Army tartan (when I can afford the purchase), and I might someday have a Navy tartan kilt to honor both my grandfathers' service in WWI. Even a district tartan I would like to have some kind history to wear it, even if it's only that a branch of my family lived in the region for a few years. For instance, I've got a kilt in the German National tartan ordered, because my mother's mother's family is German all the way.

Note, that this is only for custom made kilts. I'm not counting the easy to get kilts in stock tartans like those at Stillwater. I'll wear those because they are fast and easy to get.

Of course, this has nothing to do with anyone else, just my own preferences.