From first elections in 1952 until 1967, election cycles in States and the Center matched and all were held together.
From 1967, due to emergence of regional parties and the coalition era, state governments were dissolved without fulfilling full five years of their mandate. This led to non matching of election cycle in India.
Problems with staggered elections
Expensive: Election Commission in its report to the Law Commission has estimated that cost of holding multiple elections would be almost 50% lower than holding staggered elections
Hold on developmental activities: Due to MCC coming into force, various development activities come to a hold.
Deployment of government officials and security forces
Communal forces and immoral activities due to money power and musle power increase
Continuation in developmental policies and programs
Saving government apparatus from regular deployments on election duty
Reduced money power and muscle power use
Challenge to the federal structure of India
Voters tend to vote for same party during elections at the same time
National issues will dominate the agenda and regional issues will take a backseat