Why is triggered summon good in the crystal beast deck?

Why is triggered summon good in the crystal beast deck?
Triggered Summon is used in the Crystal Beast decks for setting up for Crystal Abundance, Ruby Carbuncles effect for when she gets special summoned or Rainbow Dragon or just filling up your field. You can use it for Pegasus' effect too. Umm guess that's it, btw i use it in my CB/ rainbow dragon deck and I've lost about 2 times and got Rainbow Dragon out about 7 times so far using triggered to help;