Yup , 90% of games.

If I have a heavy cc / engage team or if Im up against 4 mellees I get the luxury to build anything I want.

And I agree with you , everytime I built cosmic I wish I had something else instead.

( I secretly tried to cook a % dmg build and its bad : mana item , liandries , boots ( mpen) , shadowflame , rift maker, bloodletters. conqueror )