User blog comment:Sifter66/More Tear of the Goddess item paths/@comment-25055899-20140922190132

Adding tear-style conversion of mana->health, mr, or armour, would make tanky mana characters like Singed, Ryze, or Kassadin potentially more overpowered. This could be slightly avoided by making them mutually exclusive (not sure if Manamune and Archangel's Staff are already like that) but singed would still be too strong.