Abstract Art?

Here are a few abstract sculptures that I saw at the Grounds for Sculpture.

What are your thoughts on Abstract Art? I wish that some artist would explain what the piece means to them and then maybe I could understand it a bit more.

The 1st and 4th piece I am not sure about.  The 2nd and 3rd one, I can imagine different stories about what they are or can be used for.

~~

~~

~~

~~

What do you think?