The legitimate interests of those who established these nonconformities are recognized in this chapter by permitting such nonconformities to continue, subject to regulations for and limitations upon their completion, restoration, reconstruction, extension, and substitution. It is recognized, however, that nonconformities substantially and adversely affect the orderly development, maintenance, use, and taxable value of other property in the district — property that is itself subject to the regulations of this chapter. In order to secure eventual compliance with the standards of this chapter, it is, therefore, necessary to strictly regulate nonconformities and to prevent the re-establishment of nonconformities that have been discontinued.