I attempted building a pirate ship, and I noticed that the blocks would not align evenly with other blocks due to the sway of the boat on water. So I would constantly have to redo them. There would be gaps and misaligned blocks. You would notice more when you placed the square blocks in a line. I made it better by watching the ghosted block sway and I would click when it looked good, but they still weren't perfect like when building on solid ground.