Failure mode

Failure mode is a term for a, usually common, way things fail when attempting something. for example, confirmation bias is a common failure mode in reasoning.

Knowing and understanding possible failure modes in what you attempting to do is important in order to avoid them. Security Mindset and Ordinary Paranoia discusses the difference between finding and fixing failure modes by trying your best to imagine all the ways your system could fail ("ordinary paranoia") vs having a tight argument that your system does not fail (under a small number of assumptions which are each individually quite probable).

See also: Postmortems & Retrospectives

Other Examples: 
Bias
Planning Fallacy 
Status Quo Bias
Affect Heuristic
Aversion/Ugh Fields
Bucket Errors
Compartmentalization
Confirmation Bias
Fallacies
Goodhart's Law
Groupthink
Heuristics & Biases
Mind Projection Fallacy
Motivated Reasoning
Pica
Pitfalls of Rationality
Rationalization
Self-Deception
Sunk-Cost Fallacy
Paperclip Maximizer
Moral Mazes
Replication Crisis
Moloch
Tribalism
Simulacrum Levels
Information Hazards
Pascal's Mugging
Akrasia
Procrastination

Posts:
Guessing the Teacher's Password
Expecting Short Inferential Distances