We know that Bihar & Bengal has the highest population density in the country with 1109 & 1087 people living per sq km respectively & thus always been able to hold a key position in terms of Rly infrastructure development...These two states has the highest track km/sq km population area but still Bihar is in the upper edge & has more infra development in rlys...Reason is a large portion of these two states has been Single Line & density of goods train also very high.So whenever a passenger train is loop lined to through pass a freight people of Bihar never protests & accepts the delay & operational preference..But that has not been the case with Bengal...even if trains are delayed by few mins,people dont even think twice before vandalizing Rly property & thus Rly has to forcefully give first preference to pass trains & then goods...So due to operational reason...
more... running of trains has been more profitable for rlys in Bihar so they have developed rail infrasructure more than Bengal.
PS:This post comes under the light of vandalizing Rly property,disrupting rail services through the Main Line of NF Rly yesterday @ Kolaigram Station,W.B. because of a loco failure in a jam packed DEMU train.