The red herring fallacy occurs when an arguer switches from the original thesis under debate to a (usually) plausible but ultimately irrelevant thesis. It is a form of distraction that may cloak the arguer's failure to address the original topic of concern.

Here is an example:

Alex's boss tells him, "You are being reassigned, and you will need to move to Iceland."

Alex replies, "We only have three employees in Iceland, whereas I am managing 40 people here. So, what is the valid business reason for moving me to Iceland?" ​The boss replies, "Besides the great waterfalls, did you know there are hot springs in Iceland?"

Alex's boss is attempting to shift the topic to the natural phenomena of Iceland rather than answer the point that Alex has raised.

This fallacy is named "red herring" after the practice of dragging a heavily cured, strong smelling fish across a trail to throw off the scent when dogs are attempting to track something. It has the sense of "throwing off track". As such, it is a failure to properly engage in a debate or conversation.