You get paid out when all the people before you have been paid, and when there is enough money in the pot to pay you.
For example:
Person 1 deposits 1 BTC (return 1.40) Money in pot: 1 BTC
Person 2 deposits 1 BTC (return 1.40) Money in pot: 2 BTC - Person 1 gets paid out, reducing the money in the pot to 0.6
Person 3 deposits 0.5 BTC (return 0.7) Money in pot: 1.1 BTC
Person 4 deposits 1 BTC (return 1.40) Money in pot: 2.1 - Person 2 gets paid out, reducing the money in the pot to 0.7
And so on. There's no guarantee you will be paid.
Thank you kindly for your example sir. You have solved all of my quandaries. Give me an address and I will donate half a bitcoin to your cause
FaerO