For example I looked up Kenyon Martin today. I remember him being an all-star so I figured he must have had multiple 20/10 seasons. Turns out he never averaged more than 17 ppg and only got 10 rpg one season.
Muggsy Bogues surprised me positively. I thought he was just a role player like Early Boykins. Turns out he had several seasons averaging over 8 apg and a couple seasons averaging over 10 apg.
To be fair, had his career not been cut short due to injuries, he most likely would have been on that list of greats point guards.