The 3 main ways Inferior Te manifests itself in INFPs is by
- projecting their unconscious fears of incompetence becoming hypersensitive to others' mistakes
- making judgments that are overly categorical, harsh, exaggerated, hypercritical and often unfounded
- overwhelmed by the urge to take some precipitous action, usually to correct some imagined mistake which often then exacerbates the problem
I know it's not easy to understand.
You really need the book.
According to Quenk, an INFP tends to emerge from the grip of the inferior as they learn a new perspective from which to view their situation.