Because it casts a whole bunch of spells for free at the beginning of your Storm turn, because almost all of the effects are Suspendable on turn one, and lastly, because almost all of the effects are either--you guessed it--draw or ramp
BPhillipYork: 2 card impulse draw per turn, play not cast, and its got double strike, and it will trigger off your own Goblins and Orcs in addition to itself is a lot
That kind of low-risk, high-reward proposition means these Virtues are going to see play anywhere that the enchantment side is valuable, and the most widely-valuable one for Standard is Virtue of Loyalty
Not only has the team made efforts to scale aggressive cards to the multiplayer format, but it has also made a real effort to untether Dimir from its somewhat narrow identity as a perceivably un-fun or spikey combo kind of deck that is less at home at more relaxed tables
Essentially its a pay to win game and only in a very tempered group that sticks to formats and limiting budget does the game become reasonably fun
Then theres Zidane, Tantalus Thief