The conjunction fallacy occurs when people estimate that

combining two past decision$-$making strategies will yield better outcomes than committing to just one strategy.

extra information, such as a detailed breakdown of the pros and cons of each choice, will be helpful to their decision$-$making process.

the odds of two uncertain events happening together are greater than the odds of either event happening alone.

a person having stereotypical traits for a given profession is more likely to be a member of that profession.