What is coherence of technical writing?

Coherence is the unifying element in good writing. It refers to the unity created between the ideas, sentences, paragraphs and sections of a piece of writing. Coherence is what gives a piece of writing its flow. It also gives the reader a sense of what to expect and, therefore, makes the reading easier to follow as the ideas appear to be presented in a natural, almost automatic, way.

When writing lacks coherence, the reader is forced to stop and reread. Occasionally, the reader may just give up out of frustration.

Definition:

A quality of sentences, paragraphs, and essays when all parts are clearly connected. Adjective: coherent.