The worst NBA coaches of all time are some of the worst basketball coaches to take the reins of professional basketball teams. They will always be remembered for their contributions to their individual teams but not for the championships and high winning percentages. Plain and simple, these worst National Basketball Association coaches set the bar for how not to coach professional basketball teams.
Similar to the worst NHL coaches of all time, many of these bad NBA coaches had stellar playing careers but when their playing days were over and they made the leap to coaching, things didn't go so well. Isiah Thomas had that exact experience. He had a record-setting career as a player with the Detroit Pistons but his experience as the President of Basketball Operations with the New York Knicks was far from positive.
For other bad NBA coaches, the records they set were for having the worst teams in the history of the league. Sidney Lowe for example tallied a .257 win percentage between his coaching stays with the Minnesota Timberwolves and the Grizzlies in both Vancouver and Memphis. Bill Hanzlik was even worst when he won only 11 of 82 games with the Denver Nuggets in the 1997-98 season. Jim Todd however takes the cake with his 4-33 record coaching the Los Angeles Clippers in 1999-2000.So for whatever reason, all of these worst NBA coaches of all time share one thing in common, at one point in their professional basketball coaching careers they absolutely stunk. But like the worst NFL coaches of all time, many have been given a reprieve and have since gone on to see success with other teams and even at other levels. If nothing else, that should show that if you're passionate about something, don't give up on it! It might not go so well in one situation, but that doesn't mean your next attempt will turn out the same way.