Super Smash Bros. Wii U and 3DS Discussion

"I understand that DLC could add a lot to the appeal of Smash Bros.," Sakurai said, "and I appreciate that a major part of the excitement for these games come from which characters will appear in the roster, so I think fans could really enjoy DLC that could keep this excitement going. However, I think there might be criticism that we are cutting up content to sell characters one by one, or that we are adding things later that should have been there from the start.

"Creating a single fighter involves a huge investment, and we've already been giving it our all and investing a lot of work in the characters currently available in the game and, I think it’s an incredible package in terms of the sheer amount of content in the game. But it might be that people may not understand and may think that I am not offering enough by just looking at DLC itself.

"In light of this, we always need to weigh up both sides of this topic and carefully consider whether it really is best to have DLC or not.

"However, what I can say now about paid DLC is that we aren't working on anything at the moment," he continued. "We’ve put all our efforts into making the actual game. Creating DLC would involve large additional costs and require the involvement of a lot of people. I can't yet give you an answer about whether the price would justify the costs and criticisms mentioned above."

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Basically people whining about DLC has put Sakurai off the idea of making DLC.
I've even seen people complain about the Mario Kart 8 and Hyrule Warriors DLC, saying that they should have been in the base game, which is bullpomegranate as it was all developed afterwards.

I guess people are just so jaded after other gaming companies handled DLC in a really bad way (like Destiny)