Quark is one of the best parts of Star Trek: Deep Space Nine. He's one of the funniest, yet most insightful characters in the franchise. He's quick to point out complex hypocrisies, in the same breath that he's making a sarcastic remark. He's truly one of one in the Star Trek franchise.
Yet, his best moment wouldn't come until the penultimate episode of the franchise. In the seventh season episode, "Dogs of War", Quark finds out some troubling news. The Ferengi on Ferenginar have decided to change their way of life. Instead of being purely profit-based people, they are instead going to start caring for everyone on their home world through social programs. Much like the United Federation of Planets do.
Not only that but equal rights will be given to the female Ferengi. A truly progressive time for the people. Yet, Quark is having none fo this. In fact, Quark believes (through a game of telephone) that he is set to become the Grand Nagus, the person who leads the Ferengi in essence.
Yet, Quark wants nothing to do with the changes coming to his home world. So much so that with the highest honor of his people knocking on the door, he's ready to turn it down. Claiming that he won't lead his people into an era he doesn't agree with.
This culminates with one of the best lines in all of Star Trek history; "The line has to be drawn here! This far and no further!" A truly brilliant line, delivered profoundly and originally. Yet, in true Quark fashion, it wasn't his line. Quark's actor Armin Shimmerman delivered the line so profoundly that if you were a first-time fan of Star Trek, you'd think he was the one who made it famous.
But, he didn't because Quark stole the line. The Ferengi known for his devious tactics in procuring wealth, even if it screwed someone else over, once again lifted something that didn't belong to him. That iconic line. A line so iconic only the most famously captain of the generation could've delivered it.
Jean-Luc Picard. That's right, Picard dropped that banger of a quote in the 1996 film, Star Trek: First Contact, when he was ranting and raving about stopping the Borg. It was brilliant then and three years later, it was brilliant again.
Needless to say, Quark's rendition of Picard's famous quote didn't have the same dire consequences. Picard was fighting the Borg, attempting to stop them from assimilating Earth, while Quark...well...he wasn't even the person being looked at as the new Grand Nagus. It was his brother, Rom, the man who "didn't have the lobes" for such a job. At least, that's what Quark always said.
So Quark's meltdown was for nothing. Which, is almost the most perfect reason for Quark to have a meltdown.