The U.S. Navy is looking to dump the LCS for a better, more capable frigate | SOFREP

It takes a few years to actually go from a concept to a actual vessel in the water. As construction is underway on a new class of vessel, there is always a ton of " re-work" to be done simply to make the pieces " fit". Often once tested its discovered the performance is not up to what was expected. Through in different advances in technology and changes in mission and there can be a huge change in designs.