Remember, on the other end of that drive-thru speaker is a human being. Check out the things customers do that make fast-food workers crazy.

Have your order ready

In order to keep this food fast, it helps employees when you have your order ready. “I can’t tell you how many times a car pulls up to the drive-through containing five people, none of whom know what they want. It takes forever and holds up the entire line, angering the cars behind them who take it out on me,” says Marisol, who worked at a McDonald’s for two years.

Set realistic expectations

Fast food isn’t fine dining. While employees generally strive to provide the best service and product possible, the quality is only as good as provided by the franchise. “At a fast food chain, the quality is the same across the board because we’re usually getting our ingredients from the same source,” says Jason, who worked at a variety of fast food chains for three years. “Don’t expect filet mignon when you’re ordering a burger off the dollar menu.”

Speak clearly

If the employee on the other end of the drive-thru speaker sounds muffled, imagine how you sound when they’re trying to take your order. Getting annoyed when you need to repeat an order helps exactly no one—least of all, yourself. “We want to get your order right, so we may ask you to repeat yourself to get the details correct,” says Jason. “We’re not trying to insult you when we ask for clarification on an order.”

Special requests are going to take time

If you want your fries “fresh,” it’s going to be a minute (or more). A common grievance among fast-food workers seems to be when customers insist on fresh fries, or try to duck and dodge those they don’t deem fresh by requesting them without salt (which then forces the fry cook to make a separate batch). “Especially during the lunch rush, we’re constantly moving orders along, so the fries are nearly always ‘fresh,’” says Louisa, who worked in fast food throughout high school and college. “If you want something specific, you’re going to have to be patient for it.”

Find out how your favorite fast food chains got their names.

Treat others as you want to be treated

“Just because we’re serving you burgers and fries doesn’t mean we’re less of a person than you are,” says Molly, who works part-time at a Carl’s Jr. in California while going to school to earn a bachelor’s degree. “I hate when customers treat me like I’m stupid or beneath them because I’m taking their order.”

Keep your kids in check

Yes, fast food means a casual dining environment, but that doesn’t mean you should leave behind a mess of gigantic proportions. “I’ve seen parents allow their kids to spread ketchup and other condiments all over tables and chairs, not bothering to clean up the mess they’ve made. We are there to clean up after you, but that doesn’t mean you should go out of your way to leave a disaster behind,” says Molly.

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This article originally appeared on Reader's Digest.