In the first round of Jeopardy there is 18,000 dollars available in 30 questions. However, there is also one "Daily Double" hidden in there too, which gives you the opportunity to wager some or all of your money. This gives you the chance, if you bet it all and get it right, to double your money. If the Daily Double is located under one of the 200$ questions, and you just happen to pick that question last, you can come out of the first round with a whopping $35,400 and two very unhappy competitors.
In the second round all the prices double, so there is the opportunity for you to earn an additional $36,000. However, this round also has two of those magical Daily Doubles. If you answer every question in the second round except the Daily Doubles, and those magically happen to lie under two 400$ questions, you can earn up to $140,800 dollars in the second round. However, if you do the same thing, but have also played a perfect first round, that money doubles in each of the Daily Doubles too. Play perfectly through the second round, and you are walking into the final jeopardy with $282,400.
Final Jeopardy gives you one last chance to double your money, if you risk it all and get the answer correct. Since you're on such a roll until this point, you may as well, right? Get it right, and you've walked out of Jeopardy with a one-day winning total of $564,800.
I have my suspicions that if the second round ends, one player has a perfect $282,400, and the two other competitors have zero or less, they probably won't even have Final Jeopardy.