Prime Day shopping events to entice cautious consumers and play defense against stiffer competition from the likes of Walmart Inc., Target Corp. and TikTok, who have launched their own discount days in response.

Amazon Prime Day sales looked bumpy at first this week, with year-over-year comparisons for the first two days down. But by Friday, early data showed solid sales for the tech giant despite economic uncertainty.

The event, started in 2015 as a way to hook new Prime members, has pushed other retailers to launch counterprogramming.