The acquisition of private property for eminent domain usually proceeds on a long timeline. Before the government actually uses eminent domain to acquire private property, there is a substantial amount of planning. During the pre-condemnation period, which can stretch for years, a governmental entity often has the opportunity to make land use decisions about property that it intends to acquire.
While there is nothing out of the ordinary with making land use decisions pending condemnation, per se, it can become problematic when those decisions lower the value of the land that will eventually be taken. In those situations, there is a question about whether the property owner in that situation can recover from the diminution in value.