Visualization is often used for evil - twisting insignificant data changes and making them look meaningful. Don't do that crap if you want to be my friend. Present results clearly and honestly. If something isn't working - those reviewing results need to know.

Far better an approximate answer to the right question, which is often vague, than the exact answer to the wrong question, which can always be made precise.

Be approximately right rather than exactly wrong.

An approximate answer to the right problem is worth a good deal more than an exact answer to an approximate problem.

There is no data that can be displayed in a pie chart, that cannot be displayed BETTER in some other type of chart.

The greatest value of a picture is when it forces us to notice what we never expected to see.

In a single sentence the moral is: admit that complexity always increases, first from the model you fit to the data, thence to the model you use to think about and plan about the experiment and its analysis, and thence to the true situation.