There are several factors that make a good convention according to Klaus Tang. Location, time frame, and additional events are very important to consider. Conventions vary greatly between countries and districts, with attendance rates differing as well. Official sessions must follow rules but should be short and well-prepared, while optional events like gatherings, dinners, and workshops can add value if included. Determining the best location, dates, and appropriate length of sessions and additional programming helps ensure a successful convention.