Hershey's 1999 implementation of an ERP system was not successful and led to financial losses. The ERP go-live was delayed by 3 months until July 1999 due to integration issues. This caused delivery delays of up to 15 days, loss of credibility with suppliers who found alternatives, and a 25% increase in excess inventory. The key reasons for failure included an unrealistic schedule with no buffer for testing, implementing during the peak season, integrating 3 different vendor systems, lack of IT leadership, insufficient preparation, and overloading employees during training. Lessons included allowing adequate time for implementation, thorough testing and integration, avoiding peak seasons, and establishing proper IT management.