The Mystery Behind AI’s “Purple Problem” Revealed

Why do all AI-generated interfaces share the same color scheme? Even GPT-5 can’t escape this trend.

Adam Wathan, founder of Tailwind UI, just made a confession: 5 years ago, he set all buttons in Tailwind UI to bg-indigo-500 (blue-purple), and now every AI-generated interface on Earth uses this exact color.

This isn’t a joke. From GPT-5’s demo interface to various AI tool outputs, everything is blue-purple. Even castles are purple.

The reason is surprisingly simple: AI models trained on countless websites built with Tailwind UI, where the default color scheme is blue-purple. As a result, AI learned the “common sense” that “creating interfaces = using blue-purple.”

Someone pointed out an even more concerning cycle: As more AI-generated websites emerge (all in blue-purple), future AI models will train on these sites and generate even more blue-purple websites… This could potentially lead to a “blue-purple singularity.”

Adam himself seems helpless about the situation: “At the time, I just thought the color looked nice, and everyone was using it.”

Now blue-purple has become the signature of AI-generated content. Some argue this is actually beneficial — at least you can immediately identify AI-generated work.

What’s particularly interesting about this phenomenon is how a seemingly insignificant design choice ultimately influenced the entire visual style of AI-generated content. And it’s unlikely to change in the short term, as the data has already been trained into the models.

Default design choices have more power than we imagine.