Light-responsive liquid crystal polymer network (LCN) films allow for precise spatial and temporal control of the actuation and the ability to generate desired deformation by programming the microstructure. One of the mechanisms proposed for the deformation is the dynamic trans-cis-trans isomerization cycles of azobenzene that push the network away from its equilibrium and reduce the density. In this work, we use molecular dynamics simulations to unravel the physics underpinning such light-induced deformation caused by the dynamic trans-cis-trans isomerization cycles. We employ two approaches, cyclic and probabilistic switching of isomers, to simulate dynamic isomerization. The cyclic switching of isomers confirms that dynamic isomerization can lead to density changes at specific switch-time intervals. The probabilistic switching approach further deciphers the physics behind the non-monotonous relation between density reduction and intensities observed in experiments. The simulations show that an optimal combination of these two probabilities results in a maximum density reduction corroborating the experimental observations. At such an optimal combination of the probabilities, the dynamic trans-cis-trans isomerization cycles occur at a specific frequency causing significant distortion in the polymer network, resulting in a maximum density reduction.