Frustration is a product of desire turning into anticipation and expectation. It is based upon the inability to wait for that which will come with divine provenance at the correct juncture in ones incarnate existence, again being a link to the physical.
Frustration is also borne from the inability to succeed in ones plans. In this instance it is the result of not adapting to the opportunities that are presented to oneself to experience, learn and evolve by overlaying them with preferred outcomes rather than actual outcomes.
Frustration can be avoided by expecting nothing whilst accepting everything, living in the product of the divine plan.