Coherence in a draft can suffer from three kinds of shifts:
Point of view and verb tense in academic writing
Related topics:
Shifts from indirect to direct questions
Shifts from indirect to direct quotations
first-person point of view I or me (first person singular), we or us (first person plural); the perspective of the writer.
direct quotation An exact representation of what someone spoke or wrote; it is enclosed in quotation marks.
indirect quotation A statement that reports something someone said rather than quoting the exact words.