"In the spring, at the time when kings go off to war, David sent Joab out with the king's men and the whole Isrealite army. They destroyed the Ammonites and besieged Rabbah. But David remained in Jerusalem..." -2 Samuel 11:1
This is the precursor to King David's great sin--his adultery with Bathsheba and the murder of her husband, Uriah. The entire passage is prefaced with this thought: the simple fact that David was not where he was supposed to be. He begins the entire story with neglecting his duties, being lazy and abusing his power. How could things NOT go wrong?
Most great sins, I would argue, start this way. One bad decision deserves another afterall. Abraham let his wife get pawned off on a king not once... but TWICE, because he made the mistake of going into foreign lands and then lying about the relationship he had with Sarah; calling her his sister. Why did this happen? Because he was in the wrong place at the wrong time: Egypt, the anti-promised land.
But the opposite is also true. Take Samuel himself as an example. Right place at the right time with the right attitude. And so it goes throughout Scripture. Things do not start big. They progress, they escalate. Sins and victories both. They stack on top of each other. Make sure you are in the right place doing the right thing-- or you are going to get sucked down.