I was in charge of launching a line of licensed candles for a company and let me tell you - the myth of candles being relaxing is highly exaggerated.
Candles aren't manufactured like any of the other products I had worked on up to that point. Everything from where in the world they can be manufactured, to predictable burn times, cost / size ratio, ideal storage temperatures... not to mention licensors being very cautious about people being able to "burn" their IP were all factors I had not dealt with prior.
Thankfully I had great licensors to work with (Marvel, DC, Game of Thrones and Harry Potter) and I was leading an amazing team. In the end the product was very well received and every design in our initial wave (10 designs total) sold out.