Flaps, as you get near the edges of tech, to go from leading edge to new stuff, the risk in a program grows ... and sadly, one can only estimate what that risk is as one doesn't know until one gets there.
AS the level of tech increases in complexity, so too does the price of the unknown and failures induced by same as project push back the edges of the possible.
There are things that can be done, but there are also things that can't be planned away. What I think happens most often is that a groupthink occurs in order to get started. Management, funders, and those in the trenches conceptually minimize how hard the unknown can be on us during a project. It is hard to quantify, as we don't have the data points yet, but we have to get started or we never get there.
Damned if one does, damned if one doesn't.