The lottery works in mysterious ways. For naysayers of the tank, here's an article from 2017 that shows which team had the worst record and which ultimately got the #1 overall pick.
Between 1985 and 2016, only 6 teams with the best odds got the top overall pick. (6/31 is a little less than 20%).
On the other hand, 9 teams with 6th or worse odds got the top overall pick. I've alluded to this before, but being lucky really can transform a franchise.
In 2014, sure Lebron came back to Cleveland. But by virtue of winning the lottery (with 9th best odds), they were able to draft Wiggins who they basically flipped for Kevin Love. Without Kevin Love, Cleveland wouldn't have had the critical 3rd piece to make it to the finals all those years and win a title.
In 2011, Cleveland was also extremely lucky. Sure, they had acquired the Clippers pick (8th best odds) and won the lottery, enabling them to draft Kyrie Irving, another piece critical to their championship season and countless finals.
In 2008, Chicago won the lottery from the 9th slot, picking up Derrick Rose, the youngest MVP ever. While injuries derailed his career and upside, in those first few years of his career it looked like Chicago would be poised to be a contender for years to come.
(As we monitor KP's career from afar now, we'll see if we're ultimately fortunate that he got injured, as that helped put into motion what could be an epic FA summer and what is hopefully better than a #5 overall pick)
https://www.usatoday.com/story/sports/nba/draft/2017/05/16/nba-draft-lottery-history-no-1-overall-pick/101752858/