Einstein gave two conflicting interpretations of the Lorentz transformation for time, τ=t√(1-v2/c2), applied to a moving clock. The first was as a coordinate transformation, which was the basis of its derivation. The second was as a physical slowing effect on the moving clock caused solely by its motion relative to a stationary reference clock. These interpretations are not independent. That is, the Lorentz coordinate transformation cannot be applied during the clock’s time of motion without correcting for the lack of synchronization between the moving and stationary clocks resulting from the slowing of the moving clock. Otherwise, the Lorentz transformation gives an incorrect result. In addition, the interpretation as a physical effect has seemingly insurmountable logical difficulties, as it subjects the moving clock to a physical slowing dependent upon an arbitrary inertial reference frame, and which is therefore indeterminable. This interpretation is supported by questionable experimental evidence.