This sentence has five words. Here are five more words. Five-word sentences are fine. But several together become monotonous. Listen to what is happening. The writing is getting boring. The sound of it drones. It’s like a stuck record. The ear demands some variety. Now listen. I vary the sentence length, and I create music. Music. The writing sings. It has a pleasant rhythm, a lilt, a harmony. I use short sentences.…
I remember reading this as a child (maybe in elementary school) and it affecting my writing. I have to admit, especially when writing something technical, forgetting about this and focusing on making small, easily-understandable sentences can help the reader. (even though it's more boring)
For technical writing, "no more than one thought per sentence" works quite well in my opinion. Or at least it's a good guideline to apply in the first pass of proofreading.