During the trial it was revealed that McDonald’s knew that heating their coffee to this temperature would be dangerous, but they did it anyways because it would save them money. When you serve coffee that is too hot to drink, it will take much longer for a person to drink their coffee, which means that McDonald’s will not have to give out as many free refills of coffee. This policy by the fast food chain is the reason the jury awarded $2.7 million dollars in punitive damages in the McDonald’s hot coffee case. Punitive damages are meant to punish the defendant for their inappropriate business practice.
I’m smoking science and facts. Sorry you’re too stupid to understand them. One source: https://dcs.az.gov/sites/default/files/media/Child-Abuse-Tips-Scald-Injuries.pdf
Another source, citing 3 seconds at 140F: https://antiscald.com/index.php?route=information/information&information_id=15
Another source, a graph showing time to burn at liquid temperatures ranging from 130F to boiling: http://www.accuratebuilding.com/images/services/charts/hot_water_burn_scalding_lrg.gif
Edit, hey! Just for fun, here’s one specifically talking about the optimal drinking temperature for hot beverages. It only briefly mentions that the usual serving temp of coffee (~180F) can easily and quickly cause significant scalding, but it goes on to show that the optimal - in terms of customer satisfaction, taste, and safety - is a cool ~140F. https://www.sciencedirect.com/science/article/abs/pii/S0305417907002550?via%3Dihub