When looking at the turnovers, by far the most telling stat is the TOV%, an estimate of TO's committed in 100 possessions.
TOV%
Turnover Percentage (available since the 1977-78 season in the NBA); the formula is 100 * TOV / (FGA + 0.44 * FTA + TOV).
Raw numbers won't help you much, they rarely do. Isaiah possesses the 10.2 TO%, in correlation with his high usage% that is elite, simply no other way to look at it. Harden is at 19.8%, WBrook 15.8% and the point god CP3 is at 14.2%.