Units can help you better understand a question because it can help the problem be more "real life" and the ability to comprehend it will become simpler also. If doing a difficult question, solving a difficult inequality, for example, coming up with units to fit it may make going through the process of understanding it easier. For a problem that involves measurements, units can make it seem like a probable event that will unconsciously propel you to want to understand how to figure out how to reach the solution to a question. That is why units can be quite helpful in understanding a question.
Units sometimes get in the way of solving a question because they are a possible distraction to the real task at hand. In geometry, the different units can make conversions confusing, and the squares and cubes not help the solution be more clear.
