Ask HN: Which Terrible Products/Services Have Succeeded?

As in, which poorly made, poorly thought out products or services have ended up becoming wildly successful because of either good marketing, brand recognition or simple ability to understand their target audience?

Any examples? Cause if we've discussed great products that failed and better ones that failed due to a lack of marketing (https://news.ycombinator.com/item?id=19625319), we may as well discuss the opposite too.