I thought Deca Sports 2 bombed? Seems to me that they're no longer selling well.
Such games probably don't need to sell well in order to make a profit. If it's true that they work on commission when Nintendo publishes any of their games, then Hudson receives 100% of its profit when they develop and publish it themselves. Not to mention that when they create a game for Nintendo, it would have to meet a certain quality threshold in order to see release.
I think mario party 8 is managing to sell so well BECAUSE Nintendo hasn't gone out and undercut it with a sequel. They're just gonna let 8 sell year after year after year...
Yes, but previous entries in the series were always released even when the current entry was selling well. This actually means they may have been paid a fixed amount for each title, and that's why they were constantly churning out more even when the current one was still selling.
Well, that explains why the Mario Party games were crap, since Hudson never had any incentive to make a good game.
You're crap!

I know what you're saying though, there's little evolution in the series with each entry.