The Atlantic Division side set a new record for the longest losing streak in NBA history, slipping to a 26-game run of defeats during the campaign.
Harris, who bought the team in 2011, told NBA.com: "I think the season has been a huge success for us. We don't want to be 41-41. We don't want to be one-and-done. We want this team, this city to be proud of the Sixers. We want to be proud of the Sixers.
"All these pieces are in place to make this an elite team that will compete consistently for the NBA championship. There's no shortcuts to it. Unfortunately, it takes a long time. I'm really happy with the progress.
"Clearly, this has been a successful investment so far for the ownership group. But the reality is, I don't think we're going to sell this investment for a long time. I expect my kids to be around the Sixers. We're building this thing for the long run."
The Sixers finished 14th in the Eastern Conference.