Have to somewhat disagree with both posts here. Yes, it's not fair to call all Indian cities as over glorified slums, as we do have sections of cities that look decent. But there is a serious problem. The vast majority of our modern buildings and houses look ugly. Plain box like cement structures with ruined paint after a single monsoon. Most normal neighborhoods in India have a very third world drab look. Posters and ugly signboard everywhere, uneven streets, ugly shops. Most places don't have any decent pavements, and if they do, there are parked motorcycles and stalls placed everywhere. Overall our cities and architecture could be so much better.
I agree with you, most Indian cities look terrible.
I pondered on this topic a lot and came with below conclusion.
I think the biggest contributor to this is dirt patches on sides and leftover construction materials from finished buildings. This dirt spreads on the road and on buildings, Making everything look dirty and old.
Second problem in Indian cities is too many advertisement boards. These colorful boards gives chaotic look to the city.
In my observation any posh part of a City usually have paved footpath and concretised or proper landscaped empty space and have less number of advertisement boards. This makes those areas clean and orderly.
Another problem is unwillingness of gov to enforce basic civic rules. Things such as Illigal encroachment of street vendors and Illigal parking of vehicles makes roads narrower plus it forces pedestrians to walk on actual roads made for vehicle traffic.
Unchecked stray dog population combined with improper garbage disposal is also adding to ugliness to the cities.
Above mentioned problems are not that difficult to resolve. Unfortunately most municipal gov aren't taking this seriously.