If it becomes a creature, the creature has haste
If your commander has only colorless mana symbols, such as Karn, Silver Golem or Ulamog, the Ceaseless Hunger, you can only use lands that produce colorless mana
Whenever I read "Whenever" on a Magic card, my attention rises
But the reality is that making Magic is about trial and error, and that means that a lot of good ideas, ones that didn't quite work in the situation where they were first created, get left along the way
Since most Commander decks contain many cards that are synergistic with their respective commanders, it stands to reason that the average player would prefer to have their commander on the battlefield as often as possible