The Mega Drive had mixed fortunes. In Japan the console was out sold by both the PC Engine and later the Super Famicom. In Europe on the other hand, the Mega Drive fared considerably better. The practically unheard of TurboGrafx was extremely rare and the Mega Drive was able to outsell the SNES, finishing the generation in first place.
However, the success of the console in Europe, and as the Genesis in the States, may well have contributed to Sega's downfall. Two misjudged add-ons, the 32X and Mega CD put a huge dent in Sega's reputation, one so large that the company would never recover.