Seeing Trump's economic plan put into action over the past few weeks has made me think about a type of common logical fallacy that we all fall prey to.
The "it will get worse before it gets better" fallacy keeps people from failing at their plans and ideas. This mistaken belief says that things can't get better without getting worse, and it sees bad results as proof that the way things are done is right. Since both positive and negative outcomes can be used support the original position, this logic renders the claim unfalsifiable.
In the financial sector, investment advisers sometimes tell clients to keep their money in assets that are going down in value, saying that the downturn is just setting the stage for a rebound. Instead of side effects from treatments that aren't working, doctors attribute symptoms that get worse as part of "healing crises." This fallacy is also used by political leaders to explain away economic problems by saying that they are only temporary and are a necessary part of progress.
This way of thinking makes it easier for failed strategies to avoid being looked at critically and mentally stops people from changing their minds when necessary. If you think that both progress and failure are normal parts of progress, it's hard to tell if your plan is working.