Every condition for a good harvest was provided, and the harvest came in poisoned anyway. The ground was cleared of stones, walled against intruders, planted with the finest vine, guarded by a tower, fitted with a press to receive the yield. Then the vineyard, given everything, produced wild and bitter fruit.
The parable indicts squandered provision. A person granted structure, protection, resource, and the best possible material can still betray it and grow rot where sweetness was expected. Blaming the soil is easy; the soil had every advantage. What fails is the thing entrusted, when it will not become what its whole making was for. Receive every good gift and yield bitterness, and the fault lies nowhere but in you.