Sometimes it's documented but often I'd say it's a selling technique that works for any big infrastructure project. You give a rather low first cost projection, governments decide let's do this and after a while you correct the price up. First, people say: well that is to be expected the project shouldn't fail because of a little price hike. Then the price gets corrected again and then the sunken cost fallacy kicks in. now we are to deep in and we have to pull through. And so on. And you probably can't get price guarantees for such big projects cause no one would make a bid. It's a very flawed system. I'd like to know how often solar or windpark projects get price adjusted?

That's for the nuclear industry to figure out. But the fact that companies from different companies originating in entirely different countries suggest that it's a problem with the tech itself.

The hard truth many just don't want to admit is that there are some technologies that simply aren't practical, regardless of how objectively cool they might be. The truth is that the nuclear industry just has a very poor track record with being financially viable. It's only ever really been scaled through massive state-run enterprises that can operate unprofitably. Before solar and wind really took off, the case could be made that we should switch to fission, even if it is more expensive, due to climate concerns. But now that solar + batteries are massively cheaper than nuclear? It's ridiculous to spend state money building these giant white elephants when we could just slap up some more solar panels instead. We ain't running out of space to put them any time soon.