  We provide an explicit example of a non trivial Legendrian knot $\Lambda$
such that there exists a Lagrangian concordance from $\Lambda_0$ to $\Lambda$
where $\Lambda_0$ is the trivial Legendrian knot. We then use the map induced
in Legendrian contact homology by a concordance and the augmentation category
of $\Lambda$ to show that no Lagrangian concordance exists in the other
direction. This proves that the relation of Lagrangian concordance is not
symmetric.
