EOC R7, Q7 (Portfolio - more concentrated sector)

EOC Observation: The portfolio is more concentrated in a few sectors than in the past.

The EOC says it’s not attributed to loss aversion. What’s the potential bias may casue this consequence?

Hindsight. They will overestimate the degree to which they predicted an outcome which gives them a false sense of security which may lead them to take on excessive risk in the form of concentrated bets.

Thanks, or overconfidence?