Wanting to prevent getting injured was what's behind that decision / comment. But I guess with a gift of athleticism like that, you can't help but to use it.

Sauce:
https://bleacherreport.com/articles/10145780-grizzlies-ja-morant-says-hes-not-trying-to-dunk-at-all-to-avoid-injuries

I didn't realize he said that. Grizzlies are a fun team. 

grayruby

His air time is just crazy. Remember he said he decided to not dunk anymore earlier this season? I'm so glad he changed his mind.