There are times when a rezoning plan is not feasible, so only a few houses at the end of a residential area might be rezoned. It would seem to be a waste of time, but several streets in the same general area with new zoning can provide a neighbourhood upgrade for all streets. New businesses moving in will be willing to repair older buildings, and they will want their businesses to have plenty of curb appeal. That means they will trim trees and bushes, and they should also be willing to repaint.
Giving just a few houses on a street a makeover is often the start of a regeneration movement for an older neighbourhood. It is often done by attracting new buyers for homes, but converting to business can have the same effect. If the new companies are willing to work with city officials to keep traffic at a reasonable rate, the whole neighbourhood can benefit from their newest neighbours.