In most cases, the crown cannot be correctly reduced in size to the desired height and certain genus of trees like like Beech seldom react very well to crown reduction.
Overzealous pruning of trees to give the required effect can begin to cause rot in the main stem or limbs and encourage vigorous epicormic growth that fills up the crown as it rapidly grows back to its previous size.
Removal sometimes may be the only cost effective choice. When a client wants to reduce the height, canopy reduction is a much more tree friendly alternative than to topping.
Reduction of the canopy shouldn't be utilised to decrease the odds of a tree blowing over during adverse weather. Crown Thinning is a much better option protect against storm damage in an otherwise mechanically sound tree.
Crown reduction can be an option when the roots of a mature tree has notable decay making it a potential hazard or on a tree with historical or sentinmental value.