There is always risk in launching production (early). The question is how good is your risk mitigation.
Rumour has it that as an engineer at Toyota you will need CEO approval to make a running production design change. This puts the organisation under so much pressure to work defect free, that by culture and by process there will be only very few problems that have to be dealt with.
With Ineos, they do need to get going and prove out their production capability. They can have strict rules and processes in place, but they won’t have the experience with people and the vehicle to have the same results as an established manufacturer, even if this is not a start up plant.