The point is, if you decline an increase now-- and costs increase unexpectedly, you have a hard cap on how much you can do to adjust. This incents landlords to be more aggressive with pricing, because a mispricing now can extend to be mispriced for many years.
It also may change the equilibrium behavior, because it upsets a social norm and affects landlords' estimations of what other landlords will do.
It also may change the equilibrium behavior, because it upsets a social norm and affects landlords' estimations of what other landlords will do.