Because anything that you put enough of into a non-rotating format eventually hits the point where it becomes an issue
(Also, we dont have a five-color commander for every possible theme!) In this series, I discuss a theme, what value each color adds to it, the core colors of the theme, and then suggest a pair of commanders which each use at least one of the core colors but bring other spices to the table
Unless of course you NEED to banish that character your opponent has and youre holding a Dragon Fire
Some paradox abilities count the number of spells you've cast from anywhere other than your hand that turn to determine the magnitude of their effects
But when we started working on Shadowmoor we found we had a problem
Since Return to Ravnica, the limited player growth and increasing frequency of product releases and relevant reprints makes holding sealed product one of your worst options