When Railway Zonal HQ forms in a city/town, it gets an overall development at the cost of Railways, consequently outside railway area also the city develops a lot. Why don't Jharkhand looks for a new place instead of Ranchi.
I believe being a capital, Ranchi gets much fund for development, so as Tata, where TATA company is looking into all round development, same with Dhanbad, Bokaro etc. where Coal India and SAIL is doing the same.
If we look into some other states, where State Capital is not zonal HQ, like Bilaspur, Visakhapatnam,...
more... Jabalpur, Hajipur, etc. These places have developed a lot.
Say if in Jharkhand, CKP is the highest earning division and located on the main line, if HQ is made here, the entire place will develop a lot, places like CKP, Chaibasa, Seraikela will see huge development, other than the purpose of forming Zonal HQ in the state. There will be extra benefits, where state Govt. may not develop these places at that pace.