Reason № 1. Aesthetic 
The Subway is a beautiful and peaceful place, it  contributes to growing of “underground people” culture. There is the longest Art Gallery in Stockholm subway, which is very impressive.
Reason № 2. Economic
The Subway is an efficient place. We can’t do anything without State subsidy, but it is possible to cover all the costs if there is a big passenger traffic. It would take you only 16 minutes to get to Kommunar district from Oktiabyr’skaya square. Try to do this by taxi. How many line-taxis do we need to carry 1000 people through the city center during the rush hour?
Reason № 3. Socio-political
The Metro is the special status of the city. It is expensive and prestigious. Our city is not a capital yet, but it is not the provinces any more. Dnepropetrovsk should grow!
Reason № 4. Ecological
The Metro can reduce thousands of engines. There would be less motorcar accidents. We could breathe freely. We would have more space, peace and quiet.