Why don't I see more 2008 Toyota Corolla Seca sedans?

While the sedan sold alongside the hatchback version of the Corolla in Australia, the hatchback easily outsold the sedan. And that’s pretty much the reason you still see a lot of hatchbacks getting around, but sedans are thin on the ground. They just didn’t sell in the same numbers back in the day. Fundamentally, buyers were much more likely to go for the extra practicality of the hatchback layout.

Of course, that’s in Australia. In some other markets (China, for example) the sedan version of a particular make and model is often more popular than the hatchback variant. It’s a cultural thing, in essence.