Why Do Some DS Games Have Loading Screens?

Well I was playing Ninjatown recently and I wonder why does this game have loading screens? You can barely see it because it lasts for about a second. Then I played Garfield: The Tale Of Two Kittens on my friend's Nintendo DS and I noticed the exact same thing, it's loading screens and it lasts for about thrity seconds. I know some other DS games have loading screens and this game is on a SD Caritage handheld system so it should not have loading times.

Having loading screens on a CD or DVD or whatever other than cartiage have loading screens and that's understandable! But there's no excuse for having loading screens on some DS games. I remeber back on the Super Nintendo that Mickey Mania and Batman Forever have loading screens for no reason. Why do they have loading screens in some DS games like Ninjatown?

That's stupid. DS should not have loading screens. The screen should go black for a second or two, and then be ready to play. First reason: It's using cartridge, which have really fast read/write time. Second: It's a DS. How much stuff would this thing possibly need to load? It's not like it needs to load God of War: Chains of Olympus style graphics, the graphics are way simpler than that.

Portables in general should not have loading screens because portables are generally meant to play quick games when you're on the go.

Because some have massive amounts of files that need to be loaded that just can't be streamed in?

The answer is pretty obvious...diped

the answer IS obvious...the system cant cache all that wonder data fast enough.