One of the issues is over production, and its something a lot of us don't care much about but is a big deal for a company like Nintendo.
Nintendo may be a more valuable company and may be making more profits than Sony (we'll see), but whether those two things are true or not, N definitely has a lot less revenue. This means they have less money to toy with. When you increase production, you usually sign year-long contracts with a company who will produce a certain amount of product every month. Nintendo is justifiably concerned that increasing production continuously would lead to overstock. For example, would increasing production to 4 million a month satiate the current worldwide demand? I think we can all assume it would. However, this means that they'd also be producing 4 million a month for a long time to come, and they'd be jammed with overstock that ties up their financial holdings. That's bad! So instead, they increase production gradually, being very careful not to shoot past demand.
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