Often, all that it takes to get deported is a minor event that draws attention to your situation. Minor crimes that don't seem like a reason to be thrown out of the country can be used as an excuse to do just that.
For example, one young woman came into the country as a child, and she didn't know it was illegal at the time. She was just 7, and no one explained it to her. In high school, she finally found out.
Rather than trying to hide it, she tried to take the proper steps to establish herself as a legal citizen, but she didn't get a response from the government. She kept living her life, graduating from high school and going to college.
Then she was pulled over by a college police officer for a traffic violation. She didn't have a driver's license, as she still hadn't gotten anything back from the government about her status. She was arrested, put in jail and told she was going to be deported.
Not only was her crime very minor, and the arrest didn't even involve the immigration authorities, but she was trying to do the right thing. It's hard to fault her for not knowing what to do legally when she was 7 years old. Still, that minor arrest put the whole thing in motion.
This is just one example, but it shows you just how fast this can happen. If you're being threatened with deportation, it's very important to know the legal options you have. This is especially true if you've been trying to do the right thing and haven't intentionally broken the law.
Source: Ranker, "13 Craziest Reasons People Get Deported," accessed Nov. 09, 2016