Of all the Voynich theories, I find those suggesting it was produced through a mechanistic method to be most persuasive. Several statistical properties of the words just don't match up with any natural languages, and there is a large amount of repetition of individual words with small variations, but hardly any repeated phrases. One recent idea is that successive words were copied from early ones, with small rearrangements of the glyphs https://arxiv.org/pdf/1407.6639.pdf . As such, the text gains the characteristic of looking like a language, when in fact it is meaningless gibberish. Possibly this was done as way of fooling somebody rich to buy it; at some point it came into the possession of Rudolf II, Holy Roman Emperor, and was clearly a very desirable artifact even in the 17th century.