any early arcade games were either endless with minor changes in courses or they were very short. In order to keep the player playing longer designers made very challenging games. Often bosses were near unbeatable in a single life, this of course culminated in the final boss. However designer saw that players would quit in frustration when they died so close to the end. But if the player died right before the final boss they would put in just one more quarter,one more quarter, one more quarter, etc… So many games during the golden age of the arcade benign making impossible levels right before the final boss. For example, double dragons featured a level full of instakill traps that are seamless with the background as well as a very small ledge space to get knocked off of and be instantly killed. watch this clip at 15:08 for a few seconds to see what I mean
These super challenging levels set a standard that Nintendo would continue with their Nintendo entertainment system.