Missing opportunities, being liquidated, making money,
which one feels worse?
Losing 10 points is a momentary pain,
Gaining 10 points is a momentary joy,
But missing out means others have made money,
and you simply did not participate.
You believe that if you had held the position,
you would have certainly made that much money,
So you consider missing out as a kind of loss.
The difference between this loss and the loss from holding a position
is that a loss from holding might mean I am outperformed,
but missing out does not necessarily indicate my skills are lacking,
it just means I did not participate.