Building Space Ships underwater?

 I was writing about Arcane recently and realized that when you have an amphibian species of humans that they would likely assemble their space ships underwater because that would be easier in many ways for them. Why? Because though you would smelt and form the pieces of your space ship above water, since you can breathe underwater actually assembling it might be easier for them underwater than above water. You could float the pieces into place easier while assembling your space ships underwater. So, there would be many advantages to assembling your space ship underwater to above water. Then you likely would pump out the water from the space ship once it was assembled because you don't want to have to carry that water weight into space because that would mean extra fuel to do this.

So, unless you were someone like Flame who is an evolved Giant Northern Pacific Octopus who grew up on another planet after being a part of a group who helped colonize a planet where the humans died out from a surface disease from breathing the air on this new planet. So, Flame's people built their space ships underwater too and they also kept the sea water on board like a space ship aquarium in visiting other planets like Earth where their ancestors sprang from.