Roads,reconstruction

If you have been on the roads of nairobi lately,you will have noticed the reconstructions that have been going on. Some roads have been recarpeted,street lights have been put up and several culverts put in place. What has come to me as an odd observation is the fact that some of the roads that have been recarpeted were roads that were of fine quality while terrible roads have been left out. For instance, kipande road in Ngara Estate has been in a sorry state for a long time while Musuem Hill road connecting to Forest road has been fine yet it has been redone and ngara road left out!! What gives, i cant understand the logic behind this action.