suhail like myself works in an industry where one partner turning on can 2-4x capacity requirements and 10 other partners won't change your traffic profile much at all. It's easy to say plan in advance for growth but when there is a lot of varience in your growth then this becomes a problem. You will often find yourself overspending for unused capacity or struggling to meet new capacity. If your growth is a smooth line then yes you can say it is easy to figure out. But not everyones growth follows such a simple line.