I was there on 9/9/99, with multiple months worth of snow-shoveling money from the winter before and birthday/Christmas money from family, at the launch of the Dreamcast (which also happened to coincide with the release of Final Fantasy VIII) -- at an EGX of all places, which basically don't exist in the US anymore.
It was an amazing console filled to the brim with secrets, from VMU shenanigans toWindows CE OS custom programs. But beyond those great times with some great games -- a lot of gloomy stuff was going down between Sega and some other hardware and software manufacturers.
There were myriad reasons for the Dreamcast's failure, and the newest video from Did You Know Gaming hits on a handful of them. Whether it's issues with 3Dfx over the alleged race to complete the Dreamcast's graphics chip, piracy, or troubles with publishers like EA (which caused a sports game war), the walls kind of just came tumbling down in a gradual way.
My favorite fact? A marketing company went through 5,000 names before settling on Dreamcast.