DETROIT (Reuters) - Ford Motor ( F ) CEO Jim Farley has told employees that the automaker needs to speed efforts to improve quality and lower costs, and that manager bonuses, which are tied to those metrics, would be slashed to 65% of their total, according to three people familiar with the matter.

Farley recently introduced a new performance system where company bonuses are directly tied to progress on key goals in an effort to change the 121-year-old automaker's culture to hold employees more accountable. He made the announcement about the lowered bonuses at a town hall on Wednesday.

"I'm proud of the progress but we're not satisfied at all," Farley said in a third-quarter earnings presentation on Monday.

Ford executives said on Monday that the company would meet only the lower end of its annual guidance. Its shares fell by more than 10% on Tuesday.

"When we meet or exceed our targets for those factors - and we achieve the ambitious goals of Ford+ - the team is rewarded," a Ford spokesman said on Thursday. "We are focused on lowering our costs, improving our quality and making Ford a higher growth, higher margin, more capital efficient and more resilient business."

Bonuses may change depending on the company's fourth-quarter performance, he added.