Not only all this, but on top of your chances of getting any specific pick you also have the chances of any one of those draft slots actually producing a quality player. This is not truly random as it involves human choices, but time has shown that GMs are not perfect and predicting the proper order that players should be drafted, going from most talented career to least (injuries included), has proven well beyond anyone's capability.
In other words, not only are your odds short on getting the #1, they are even worse that you will both get the #1 pick AND that player will be the best player in the long term. Kobe, Jordan, Durant...
You don't only not need to be the worst team to do the best in the draft, you don't even need to win the best pick in the lottery in many years.
Barring a great turnaround the Pacers are going to have a shot at getting a pretty big impact player. But they'll still carry strong odds of failing to get one too.