He Bingjiao's inconsistency is an issue, her lack of experience in the senior circuit told; after all she is only barely a year into the senior level full-time and hadn't played enough tournaments, only a handful of low level ones, during her junior days. I should think it's normal to have ups and downs at the beginning of her career at the senior level - if only she had started competing in the senior circuit much earlier at a younger age like most of her peers.
In the match with Sindhu, her more experienced opponent was keeping the shuttle down and/or playing fast flat drives all the time, only lifting when necessary or forced to, which time and again forced HBJ to lift, and Sindhu was ready to quickly get behind the shuttle and pounced on it. Besides, HBJ was more error-prone today than usual, another weakness of hers that needs rectifying.
Not to worry, HBJ is a smart, thinking player, she'll get it right the next time they meet. As HBJ matures- I consider her quite mature for her age - her rise to seriously challenge the top players won't be far off, rather pretty soon.