This means you cant wait to see the result of a flip before playing a spell that might protect one of your permanents from the result of the flip
Azorius Control is a very powerful deck in nearly every format
I don't believe it saw much, if any, Constructed play at the time (I may be wrong on this, but can't seem to find anything from researching online), but the card was considered quite powerful stat-wise and featured some keywords not commonly found on Green cards
Protecting the battlefield with various counter spells and board wipes, UW Control seeks to unleash a single good threat, nearly always Dream Trawler and then keep anything from dealing with it while it does its work
Innistrad: Midnight Hunt is a set chock-full of excellent cards to play in Commander
Unless the opponent has a specific action spell to clear him from the field, he will reliably generate points every single turn until victory is achieved