Not necessarily. Objective priorities can evolve over time, new ones can come to the fore. Changing government policy when a new administration takes over can also affect the priorities. Also, many of the already started projects are long duration ones, which in practice take more than 8 years i.e. more than two presidential terms to complete. Moreover, some of these started projects were in their absolute infancy, to even the ground or order building materials before physical work starts, already qualifies as an inaugurated project. Other than that, aryobarzan's comment is valid: realization of the new projects and previous ones aren't mutually exclusive.
I agree there's a general issue with some unfinished projects in Iran, but in order to know if the recent decision by the administration will contribute to it, much more detailed information would be needed.