Why are Muslim areas in old cities so mich shabbier and dirtier than other areas?

First of all, let's address the obvious objections to my question.

1. Muslim areas - are there areas in our cities called Muslim areas? Most certainly so. Just like New York has black neighborhoods, Jewish neighborhoods, Mumbai has Jain societies and New Jersey and Texas have Indian neighborhoods. Indian cities have Muslim areas. There is nothing wrong with this. Minorities tend to cluster together. This is a universal phenomena.

2. Are Muslim areas dirty - You only have to visit areas around Jama Masjid, Okhla, Batla House, Jafrabad to know that I'm not making this up.

Now that we have established that this is a common phenomenon, I feel like I have a right to ask this question without being labeled racists or divisive or derogatory. So why are these areas dirty, shabby. More than other neighborhoods. Why do they have garbage, overflowing sewers and dug up roads.