[nickpettit]

Our data scientist at Treehouse actually tested this extensively, but it's such a complex issue (lots of qualitative/anecdotal/branding evidence that's difficult to measure) that the results are still inconclusive. Basically, it helped us and hurt us in different ways, but the long term effects seemed bad enough that we stopped.

[snowwrestler]

If after extensive research the worst you can say is that "results are still inconclusive," it is hardly a "beginner web mistake" on par with bad navigation.

I think the reason you included modal forms in your article is the same reason people are posting in this thread about them: you personally don't like them.

I would say that "substituting your opinion for testing" actually is a beginner web design mistake.

[nickpettit]

> I think the reason you included modal forms in your article is the same reason people are posting in this thread about them: you personally don't like them.

People not liking them is a form of qualitative data. That's the feedback we received from enough people to decide that it was damaging our brand long-term.