A constantly changing list would only reflect the traders' view which is not what the choices were all about. Remember that the request was for nominations of stocks to hold for a full year.
So only a substantial deterioration in business prospects should effect that list, keeping in mind that we need to and may rely on good managers to deal with ever changing business conditions.
The traders' perspective dominating posts to this board will of course disagree if only because the focus is on a different time scale, different tactics and different temperaments.