My understanding of the limitation is that a character can make one attempt at inspiration per situation/scene, and a given Rune or Passion can be used for inspiration once per Season.
So, in a given session, a character is inspired by their Earth rune when trying a communication skill. They cannot use the Earth rune for inspiration for the remainder of the session/season, and in that situation/scene where they are attempting that communication roll, they cannot use become inspired again, even for a different ability roll.
Later in the same session, the party is in combat. The character cannot use the Earth rune to inspire their Axe skill, because they have already used the Earth rune that session/season. They can, however, attempt an inspiration with a different applicable Rune or Passion, as it is a different scene or situation.
My players will prefer inspiration, specifically Runic inspiration to any other augment because Runic inspiration doesn't have the potential to make their attempt at the desired skill worse, just makes using the Rune in the future harder (or impossible in the case of a fumble).