I think most will agree that siege rams, catas and trebs are not very appealing to use especially when there are substantial defenders on the tower/keep.
It is tedious to use, it exposes you to enemy fire, you tend to be the first to die if the enemy zerg rushes out, or if you are all the way behind on the treb you miss out on all the zerg fight actions.
It can be so unappealing to use that I can see rams, catas and trebs being built but nobody steps forward to use them. Myself included.
This can be detrimental to a zerg's attempt to take an objective as the faster you take out a wall/gate, the more options you have when engaging the defenders and you allow less time for defenders to shore up their defenses.
Rams/catas/trebs users are the unsung heroes of any server like the scouts/siege-refreshers and more should be done to reward them for their effort, bravery and self-sacrifice.
So...what would be a good way to make siege rams, catas and trebs more rewarding/appealing?