They didn't, back in 2012 we had a number of key Navantia personnel from the F-105 build and when asked straight out if they had encountered the problems we were they admitted they had but hadn't informed us. Basically we had to discover every problem for ourselves, even though the selected design had been the "existing" proven option that was to be built to print with minimal requirement for local design and engineering work.
The first warning sign I recall was before steel was cut on ship one, technical officers, designers and engineers assigned to validating design elements such as equipment removal routes were finding the provided design data did not comply. There were numerous examples of elements of the design that literally did not work and when Navantia were approached about them it was usually discovered that the Navantia production team had developed a compromise work around but that this had not been fed back into the design baseline. The result of this was problems encountered on F-101 were worked around on the next three ships but then , because they had been forgotten / new production teams were not aware of them, they impacted on F-105 and Hobart.
There is a myth that BAE had no such issues with the LHDs when in truth Canberra and Adelaide followed JCI almost immediately thus benefiting from lessons learned on a hot project, but even though delivered to Williamstown on cost and schedule, problems with the local fabrication of the island blocks were remarkably similar to those encountered with the AWD blocks and in the end both shops were late and delivered with multiple defects.
