It looks like at one time someone cared enough to put boards under the tires. Hard to say what the story is. I know a lot of people who retired late in life with big plans only to have health issues that prevented following their dream.
My Dad and Mom (RIP) were those people. They bought a motorhome with plans on travel only to have health issues intervene. The motorhome sat in the drive for years before the realization that they would not be able to use it and sold it.
I imagine that same scenario is played over and over.