When I started model building the choices were pretty clear--cars, planes, or tanks. At least that is what I thought. After just a few short visits to hobby shops I came to realize that cars meant, cars, trucks, race cars, motorcycles, and other commercial vehicles. Planes meant military, as well as passenger planes. And tanks meant every piece of military hardware that has ever existed.
What makes someone choose a particular subject. For me it was my love of the 1966 and 67 mustangs. For a friend it was a love of Star Wars and old war movies like The Great Escape. Another friend loved motorcycles incredibly, but could never convince his parents to let him have one, so he settled for a shelf full of the scale replica version.
The reason is probably not terribly important. As long as there is a hobby shop to meet those needs, those needs can stretch from wide and far.
Of course, it can work the other way. A trip to the hobby shop could spur you to build something you had never considered. This is especially true if the shop stocks lots of unusual things from far and wide. I once came across a shop which sold model kits of scale versions of musical instruments. I remember one of the kits was of a replica Beatles drum kit--sadly there was no Ringo Starr figure to go with it.
As you can imagine, if you have been following this blog, I might have started out with the Mustang, but that doesn't mean that is the only kit, or type of kit that I have bought or somehow managed to add to my collection at no cost to myself. A man can get bored building only one type of kit.
I have (built an unopened) race cars
military half tracks
a Japanese aircraft carrier
a garage with tools diorama
One KFC outlet
Several train buildings
a large trailer for hauling liquids
to name a few
And the strange thing is, if I were to enter a hobby shop tomorrow and they had a kit of an old pinball machine, I would probably buy it and put in on the shelf next to the rest of them.
For me the inexhaustible variety of kits is a blessing. For the potential newcomer, I can only guess such a variety is daunting.