  We studied the dynamics of a liquid contact line receding on a hydrophobic
soft gel (SBS-paraffin). In order to realize a well-defined geometry with an
accurate control of velocity, a dip-coating setup was implemented. Provided
that the elastic modulus is small enough, a significant deformation takes place
near the contact line, which in turn drastically influences the wetting
behaviour. Depending on the translation velocity of the substrate, the contact
line exhibits different regimes of motions. Continuous motions are observed at
high and low velocities, meanwhile two types of stick-slip motion, periodic and
erratic, appear at intermediate velocities. We suggest that the observed
transitions could be explained in terms of the competition between different
frequencies, i.e., the frequency of the strain field variation induced by the
contact line motion and the crossover frequency of the gel related to the
material relaxation. Our results provide systematic views on how the wetting of
liquid is modified by the rheological properties of a complex soft substrate.
