The Nintendo 3DS' StreetPass Mii Plaza feature and subsequent minigames were created to make meeting other 3DS players feel like a single-player game, the feature's developers told Kotaku.
According to StreetPass Mii Plaza director Kouichi Kawamoto, the feature was designed to promote more use of StreetPass and Miis between users. Keeping the 3DS owner's Mii as the "only true hero" of their own Mii Plaza world is a single-player approach to what is essentially a social networking feature.
"I think the aims of the StreetPass Mii Plaza project were pretty simple: StreetPass would get used a lot more often if there was a StreetPass game included with every system, and using Mii characters in the data exchanged will help them seem more alive," Kawamoto said.
The first two Mii Plaza games, Puzzle Swap and turn-based role-playing game Find Mii, were created to make players feel they accomplished something by meeting other people — and collecting puzzle pieces and leveling up were great benefits to give players who sought 3DS interaction.
"The core concept I brought forward is the idea that gameplay advances forward when you use StreetPass," Kawamoto said. "In other words, going outside in order to use StreetPass is an important aspect of the games. I think that's an unusual experience for people. Also, I felt it important to have the Mii characters play as active a role in the games as possible. That helps players feel like the people they're interacting with really exist."
Kawamoto also noted that the reason StreetPass only allows users to collect 10 Miis at a time was to allow room for players to collect more data via StreetPass at any given time.
"We had been thinking about the possibility of expanding StreetPass Mii Plaza from the start, and we set the maximum number of connections to 10 to ensure we'd have room to exchange more data via StreetPass in the future," Kawamoto said. "As a result, if we get to a point where we definitely won't expand it anymore, there is a possibility that we'll raise the number of connections. However, we have no plans to do that, and we're already transmitting a lot of data, so even if we stopped right now, I doubt that number would go up much."