IMHO many people, even among art critics of the last century, equates beauty and value (which is as childish as thinking that beauty is good and ugly is bad).
Is often said the "Good photos are like good jokes. If you have to explain it, it just isn’t that good.", but think it would be extremly difficult to understand "a good joke" if it's based on a cultural background very different from yours.
This means, imho, that art is much more a product of interaction between the work of art and the viewer, rather than something intrinsic in the work of art itself.
In 1915 painted his "Black Square", which is, well... a black square painted on a canvas.
And it remains a black square on a canvas until you read that that painting was hanged in a upper corner of the room, a place traditionally reserved (in russian homes) to Jesus's icon.
With this information the painting acquires (in the viewer mind) a much greater meaming.
In conclusion, art is like a dialogue: if you don't understand what is said to you there is no dialogue and therefore no art, but this doesn't means that the work of art's is somehow flawed of valueless.