Why Nintendo is so stubborn when it comes to media formats?

[Bofferbrauer]

Soundwave said:

64DD was a huge mistake. They could've still salvaged that gen had they ditched that and went for a CD-ROM add-on.

The issue wasn't the vendors, I'm sure Philips would've been happy to give them CD drives, and if not them probably 10 other vendors.

The issue with CD is I think Miyamoto and several others at Nintendo hated the format and they twisted Yamauchi's arm on it, but in doing so they basically handed the console market on a silver platter to Sony. That's why game designers should not be making business decisions. 

They got scarred twice in a row with CDs, I can understand why they didn't want to get burned a third time. Besides, time was running out, had they made a new deal for CDs it would have delayed the N64 even further. Releasing a CD update didn't work out well for the Megadrive/Genesis, but the Famicom DD did fine in Japan, so that was a natural choice for an upgrade for Nintendo back then. Too bad that one failed, too. Nintendo really had no luck with formats back then.