A backlash from employees prompted United Airlines to shelve a quarterly bonus lottery plan that made it more difficult for staff to earn rewards.

"Our intention was to introduce a better, more exciting program, but we misjudged how these changes would be received by many of you," United's president, Scott Kirby, said in a note to employees.

United had been giving employees bonuses each quarter when they met certain company performance metrics. But they changed it for a new lottery program in which qualifying employees could enter to win prizes. For example, a single employee could win $100,000, while other prizes included vacations and cash rewards, according to the Chicago Business Journal, citing a company memo.

The change to the bonus program comes as United and other airlines are facing higher fuel and other costs but are also adding service.

Now United is "pressing the pause button" on the program as it reviews employee feedback, Kirby said.

Some employees were not on board with the program.

Pilots complained to their union that the change would make it harder to earn bonuses. The chairman of the union's United council met with senior executives of the airline before the plan was scrapped, said a union spokesman, Roger Phillips.

Laurie Vesalo, whose LinkedIn page says she is a United Airlines flight attendant, wrote a letter that was posted on Change.org titled "Make United Airlines Great Again." It outlined complaints about United's flight attendants' compensation and working conditions.

"They took away our quarterly incentive bonuses, and changed it to a deplorable new system that only rewards an elite few," it said. "No surprise, since they are good at only awarding an 'elite few' — aka the upper management, and not the entire population of frontline workers."

The post also complained that employees did not receive a $1,000 bonus after the new tax law passed. Other airlines, including competitors American Airlines and JetBlue, doled out such bonuses.

"Why did they get the bonus? Because they care about their employees? That's why. Novel idea," said the petition, which received 1,000 supporters.

United had about 89,800 employees, about 80 percent of them unionized, as of the end of 2017, according to a recent company filing.