That's what a greased or greaser is. To much grease was caught in the incused numeral 4 of the die. So it became compacted and hardened over time. So when it struck the blank planchet it didn't allow the 4 to form properly. So, the die was plugged
"If it isn't broken, don't fix it". These machines are like Dinosaurs., no? You'd think that they would make some remedies for these issues. Just my 2 cents.
Nothing ever created by man lasts forever. Maybe made better but never perfect. Everything breaks down and/or becomes discombobulated over time
Have you ever seen one of these "machines" in action? They'll seize-up due to the excessive friction if not lubricated. And there's debris and it sticks and then lodges, and that's all these.