Trust plays a big part of it, especially in the gaming industry.
- Trust from consumers
- Trust (and buy-in) from game developers/publishers
Getting that trust is a long and often winding path, just look at Microsoft's track record with the Xbox. There were moments along the way where it could have all fallen apart, but at least they seem to genuinely believe in the product/platform.
I never really got that impression from Stadia, I tend to follow a lot of games media and Stadia never really got that much of a mention. That might be a fault of the outlets I follow, but you'd think Stadia PR team would be the ones out there working the circuit to drum up positive coverage.
Stadia hired Phil Harrison as the leader, he's had a long history of working in the industry, but tbh I don't think google put the resources behind him.