[Beldin]

> It’s in the train co’s interest ...

But the if the trains pass first inspection, then it no longer is a development issue but a maintenance issue. [1]

It's not as if train companies can afford to run a statistically significant number of carriages from different suppliers to see which one gives them the actual best bang for buck 5 years down the road.

[1] Rule-proving exception: the Fyra trains. https://en.m.wikipedia.org/wiki/Fyra

The short version: high speed trains failed and were eventually returned (2014) to the manufacturer for ~2/3rds of new price. (That's the exception part.) There have not been high speed trains on this traject since. (That's the rule-conforming part.)