Appeal to probability fallacy
Logical fallacy
The appeal to probability is a logical fallacy that treats something as certain just because it is possible or likely. It jumps from 'this could happen' to 'this will happen'.
This is a reasoning error described in logic and critical-thinking books, rather than a bias measured in psychology experiments.
In everyday life
An investor reasons that since some startups become huge successes, the one they just put money into certainly will too.
Because millions of people use weak passwords, you tell a friend that her email account will definitely be hacked this year.
Why your mind does this
Our brains handle small, concrete quantities well but struggle with large numbers, fractions and odds. Rounding, grouping and labeling let us make fast decisions without doing the math. For most daily choices, a rough answer is good enough.
Its family, in 30 seconds: Simpler numbers
How to spot it
Listen for the leap from 'could' or 'might' to 'will' or 'definitely'.
How to counter it
Estimate the actual chance and say it out loud as a number before treating an outcome as certain.
Same family: Simpler numbers
SourceWikipedia