The reason is simple: contemporary-art collectors tend to be younger, so less estate property finds its way to the block.

Little estate property comes on the market, since collectors in the field tend to be younger.

Those collectors who do keep the art on tend to choose gentle material or exile the works to obscure corners.

Many collectors also tend to have a direction or like for certain vehicles that reflects their expertise.

Book collectors tend to frequent used book stores.

After all, museums, galleries and collectors tend to come about in concert - they're mutually dependent - and only where people have roots.

But contemporary art is scarce in estates, since the collectors tend to be young.

Moreover, contemporary art from estates is hard to come by, since its collectors tend to be younger.

Since collectors in this area tend to be younger, fewer estates come on the market, forcing experts to put together sales one work at a time.

Even his collectors tend to be private people.