What was Richard Neville 16th Earl of Warwick failures?

Richard Neville, the 16th Earl of Warwick, known as the "Kingmaker," faced several significant failures during his political and military career. Despite his initial successes in the Wars of the Roses, his attempts to control the throne ultimately backfired, leading to the defeat of his forces at the Battle of Tewkesbury in 1471. Additionally, his shifting alliances, particularly with Edward IV and later with the Lancastrians, weakened his position and contributed to his downfall. Ultimately, Warwick was killed in battle, marking the end of his ambitious aspirations for power.