It now takes an afternoon to turn an idea into something that looks like a real product. That's a genuine gift for teams who use the time well, and a trap for teams who mistake a working prototype for a validated decision.
Cheap building changes the cost of being wrong, not of being right
When a prototype takes weeks, teams are forced to think hard before starting. When it takes an afternoon, that forcing function disappears, and it's tempting to skip straight from idea to prompt to deploy.
The problem isn't speed. It's that a fast, well-built answer to the wrong question is still the wrong answer, just arrived at faster and with more confidence behind it.
Validate the decision, not just the interface
Before a prototype gets built, the real product work still has to happen: naming the problem, finding evidence it matters, understanding who feels it and why the proposed value is credible. AI can generate the screen. It can't tell you whether building it was the right move.
What this looks like in practice
A team notices a competitor added a feature and builds their own version in a day using AI tools, because it's cheap enough to just try. Nobody asked whether their own users actually wanted it. Three sprints later, usage is near zero and the team is maintaining a feature nobody asked for, because building it stopped feeling like a decision that needed defending.
In plain terms
Just because something is cheap to build doesn't mean it's cheap to have built the wrong thing. Every feature, however fast it was to make, still needs someone to use it, understand it, and get value from it, or it's just extra weight the product now has to carry. Speed changes how fast you can build. It doesn't change what's worth building.