The biggest reason people say BPs aren't good starters is if you get a picky eater..this can scare new owners who don't know if their snake is ok or not or is going to starve! Our vet said someone force fed their ball every meal...All because he missed one feeding when he got him!
As long as you listen to advice from people who have owned them..buy from a good breeder, know the animal you are buying..and of course make sure it's healthy when you buy it..You'll be fine!
Our first snake was a ball python..She was wild caught and came with ticks, scars, and RI! It was a rough start, but it was well worth it, and even with her illnesses she is still one of the easiest pets we care for! With no prior snake experience we were able to handle it with the help of people on forums like this one and since we got her better...easy!