Thinking of skimping on a DoorDash tip? Do so at your own risk, warns a message being tested by the food delivery provider.

If you try to place an order through the DoorDash app without leaving a tip, you may get this pop-up: “Orders with no tip might take longer to get delivered — are you sure you want to continue?” The note goes on: “Dashers can pick and choose which orders they want to do. Orders that take longer to be accepted by Dashers tend to result in a slower delivery.”

In other words, tip your drivers, or prepare to wait a long time for a cold meal. Customers are then given the option to add a tip, or continue without one.

As tipping screens have become more commonplace, Americans are balking at the ask — and wondering when they should tip, and when it’s acceptable to hit “no.” In this case, DoorDash is laying out the cons directly to the customer, and asking them them to see the extra money as incentive for good service, rather than reward.

The message is just a test, DoorDash spokesperson Jenn Rosenberg told CNN in an email. “This reminder screen is something that we’re currently testing to help create the best possible experience for all members of our community,” she said. “As with anything we pilot, we look forward to closely analyzing the results and feedback.”

Rosenberg noted that Dashers, the people who deliver orders, are “independent contractors” who “have full freedom to accept or reject offers based on what they view as valuable and rewarding.” Tips go directly to Dashers, according to the company. So if an order comes in without a tip, they’re more likely to let it linger.

DoorDash, along with other third-party delivery providers, has opposed efforts to create a minimum wage for delivery drivers. Its own sales have been growing.

In the third quarter, total orders grew 24% year-over-year to 543 million, the company said Wednesday. And revenue spiked 27% to $2.2 billion compared to last year. Even though the company reported a net loss of $404 million, shares of the company were up about 7% after the market closed on Wednesday.

Tips may well function as a bonus for workers. But for others, like some restaurant servers, tips are an essential part of pay. In these cases, companies rely on customers to cover their employees’ wages.

Federally, the tipped minimum wage is just $2.13 per hour (some states have higher minimums). Employers are required to make up the difference if tips don’t bring workers up to the federal minimum wage.