'After 20 minutes of him talking... I put in my two weeks': Employee quits during his yearly meeting, gets reprimanded for not cutting his boss off sooner

Sure, we all know the basic societal niceties—say please and thank you, don't interrupt someone when they're talking, chew with your mouth closed, let pregnant women and senior citizens have the seat on the bus, etc. But when is it appropriate to stand your ground and overstep those normal "niceties?" Well, according to Reddit, it's when you're quitting. 

This employee made the decision to himself that he was going to quit months ago. The job was all kids of messed up internally, and he was getting more duties and no pay raise. He waited until you had another job lined up, however, before meeting his his boss to quit. It just so happened that it conveniently fell on his yearly 1:1 meeting. He tried to make it sooner, but the manager was just "too" busy. So he went into the meeting ready to give his two weeks, but the manager would not stop talking… This was only supposed to be a 30-minute meeting, but the manager went on non-stop for 20 minutes. Finally, when OP was able to get a word in, it was simply to put his two weeks in. 

Now, the manager was mad that he didn't interrupt him, but interrupting someone when they're talking is impolite. So what was he supposed to do? This is where the lines of proper edict start to get blurred. See how it went down below. And if you're thinking about quitting, here is a list of ways to "professional" explain why.