During past few years I was lucky to observe and photograph how Black-necked Stilts were nesting. I saw them incubating their eggs between the rocks, on the ground but have never seen their floating nests.
The floating nest in the photo above was build by female and male Stilts.
Why did they chose to build this luxurious nest is difficult to say? I assume that their instinct led them to this place and "told" it's more safe to incubate the eggs in this hidden place and on the floating nest.
I am sure that the female chose the place and was determined to build a high quality nest.
Yes, it is hard and tedious work, but in the end, the chances of a safe incubation of eggs are much greater than in the open space between the rocks or in the shallow dent covered with a few sticks on the ground.
Generally, life is good.