Why didn't my clarified herb butter solidify? I was making spicy clarified butter but wanted to avoid the flecks of red or black that can throw off the color of a dish.  I decided to steep some basil and a few other herbs with an habanero in the butter and then remove them.  

The butter did not come out nicely AT ALL. Despite letting it cool for some time, the butter never re-solidified.  I was rushed and didn't have cheesecloth so I might have done a poor job at removing the solids.  At the normal temperature of my kitchen, butter, clarified or otherwise, will solidify - but not this stuff.  

Is it possible that the oils from the herbs and pepper prevented it from setting up?  

I wouldn't think a handful of herbs and a singular hot pepper would have enough oil to prevent 12+ ounces of clarified butter from setting up.
I can only guess that something from the herbs has "disturbed the balance of the mix" and is preventing it from setting.

Putting my chemist's hat on, the problem is similar to what happens when a solid reaction product forms an emulsion and refuses to precipitate. When that happens, there are ways to induce precipitation, but not all of them can be applied to food.

Try adding a pinch of salt - mix, and wait.

If that fails, smear a knife blade with some fresh butter and stir the mix with it.

If that fails, try cooling it.

If that fails, try mixing in a pinch of bicarbonate of soda.

There are other suggestions, but I assume you want to eat the butter once it solidifies. Ideally, you want to find that happening after one suggestion has worked. If it takes a succession of suggestions to find a way to solidify it, this is about as far as you can go without the product starting to "lose its intention".