Big Bang Implementation – A Big Bang implementation offers a better ROI, because it is much faster and cost-effective than any other alternative.
Phased Implementation – In this method, the full Salesforce implementation is bifurcated into various phases by which all users gradually move to groups to the new system.
Parallel Implementation – Parallel implementations are quicker than the Phased implementations and slower than the big bang implementation, however, they also have a low level of risk