A buried talent occurs because of a lack of the virtue of hope.

It's been said by saints that discouragement is the enemy of our perseverance, and it's a temptation that must be sensed at its earliest rising, and beaten over the head with hope before it has the slightest effect on our soul. 

We must bear fruit - it's a command from God - and most of the fruit God wants are simply souls closer to Christ, brought about by faith, hope, and self-costly love (mainly in generous and infinitely patient acts of sincere friendship...better conversation, less self, deeds of service, smiles, prayer for them, availability), and lots of graces from our loving Father God.