3 reasons -
1) cash coming in from biz revenues, so I spend more time on trying to put money to work, then on trying to take profit.... plus my horizon is still quite long
2) peaks are hard to read anyway... once in a while you watch many sectors and seems they all look 'toppy' at the same time, only then there is a high probability play to sell some.
3) instead of selling outright, I like to sell calls on them.. but this is dependent on the correct read of tops anyway. there is no intrinsic edge in selling calls.
