Why is Montrezl Harrell not a good defender?

[iamgine]

Athletic, check.
Hustle, check.
Effort, check.
Size, check.
Motor, check.

What he lacks seems to be height but we call PJ Tucker an excellent defender while being shorter than Harrell. To me, unlike Wiggins or KAT who doesn't have the hustle and effort, Harrell seems to have all the tools and potential to be a good defender if not great. At least PJ Tucker level. But why is he a terrible defender? Is he just...dumb?

[ArbitraryWater]

Timing, anticipation and reaction and footwork is very important.

But he is a good defender.

Jokic thing was a myth. He barely was on the floor for Jokic's buckets.

[Stanley Kobrick]

low IQ, bad rotations. i believe kawhi use to get on montrezl periodically during games because he fumbles the schematics on defense. he's a hustle player, a dumb one, but plays hard

[light]

Athletic, check.
Hustle, check.
Effort, check.
Size, check.
Motor, check.

What he lacks seems to be height but we call PJ Tucker an excellent defender while being shorter than Harrell. To me, unlike Wiggins or KAT who doesn't have the hustle and effort, Harrell seems to have all the tools and potential to be a good defender if not great. At least PJ Tucker level. But why is he a terrible defender? Is he just...dumb?

He is actually a pretty good defender.

And he was 2nd last year in charges drawn with 30 which is a lot. He took a charge in his first preseason game with the Lakers.

[Axe]

Kawhi made him look like a scrub instead of elevating him

[Manny98]

He's not a bad defender, he just struggles against true centers like Jokic & Embiid and his overall defensive understanding is on the low side but not as bad as KAT

I think Vogel can mold him into a positive defender as the things he needs to improve on are very teachable

[8Ball]

He is a good defender. Just not a good defender against large 7ft offensive centers.