  We point out that the quantum de Finetti representation, unique for
infinitely extendable exchangeable systems, assigns a non-zero Quantum Discord
to uncorrelated systems and thus cannot serve as an universal prior
distribution in the Bayesian Quantum Tomography. This apparent paradox stems
from linearity of the Born rule for the probability assignment in Quantum
Mechanics, which results in mixing of one's knowledge about the quantum state
and the representative of the state in one density matrix.
