What+is+the+purpose+of+urban+planning?

Urban planning is in charge of developing spaces to make the most of them so people can live comfortable in the cities. The urban planners create landscapes, organize groups of buildings and roads, etc. Why are there so many places so badly designed? Well, it probably has to do with that most of the constructions are made by unexperienced people with no training in design and have no intention of making a comfortable place. At the same time it has to do with the fact that urban planning is still relatively a new career. It only has around 25 years, and before that other fields took care of their job, like architecture or anything else. Since it was only 25 years ago that we realized we needed urban planners, people hasn't adapted to the idea yet.