What Happens Now?
Let's continue with the same example:
Let's examine what happens when the deal ends, using various exchange rates:

[1] The EUR/USD exchange rate is 1.1000.
In this case, the deal has been already closed at your pre-defined STOP-LOSS rate of 1.0850. You have lost EUR 100, the amount you were willing to risk.
[2] The EUR/USD exchange rate at deal end is 1.0795. You lost EUR 51.
[3] The EUR/USD exchange rate at deal end is 1.0500. You made profit of EUR 229.

Notes:
[1] The example provided is for illustrative purposes only, and does not take spreads into consideration.

[2] In real life, the exchange rates change automatically and continuously. Whenever you wish to make a deal with a specific rate appearing on the screen, it will be "frozen" for you, allowing you a few seconds to accept or reject it.