First-order thinking is fast and easy. It happens when we look for something that only solves the immediate problem without considering the consequences.
Second-order thinking is more deliberate. It is thinking in terms of interactions and time, understanding that despite our intentions our interventions often cause harm. Second order thinkers ask themselves the question “And then what?”
There are many examples of the first type of incomplete thinking — for example, personal decisions like taking a job or investing your time and money into something. Or as in society like voting in elections.
And I say 'incomplete' because even if consequences seems to be positive in the short run, it doesn't mean that it will stay positive in the long run. And more importantly, that also if it is positive afterward it will be just a matter of coincidence not based on a logical way of thinking.