What is an alternative explanation for your results? What could have gone wrong?

In a paper’s discussion section, researchers must address possible shortcomings and critiques of their own experiment. A common way to do this is to argue against one’s own hypothesis by using references to contradictory studies. This way, not only does a researcher identify a limitation or possible confound, he or she can provide direct support for this possibility using currently existing research. Following this, he or she will turn back in on the argument and reconcile their findings with those conflicting studies mentioned.

Example:
Result: We found that there were no differences in memory performance between students who were given a caffeine and students given a placebo.

Conflicting finding: Caffeine-related cognitive improvement is seen primarily in studies using coffee. A recent study suggests, however, that the memory improvement capabilities of coffee are due not to the caffeine content in coffee, but rather other bioactive compounds (Shukkit-Halehypothesis , Miller, Chu, Lyle & Joseph, 2013).
Reconciliation: Further studies should use cups of coffee (regular, decaf) instead of caffeine pills to evaluate the performance contribution of non-caffeine components.

LAB REPORT:
What is the primary finding/result of your study?

What is an alternative explanation for your results? What could have gone wrong?