When Iris 1 was initially released, it was a unique synth (essentially a poly synth using the Rx spectrograph engine.) As such, in the initial Iris 1 design, we had to make some guesses with respect to usability and experience, since nothing like it was on the market. 

After about a year and a half, iZotope knew where they wanted to take it, and decided (rather quickly, as such things go) to go straight to Iris 2, with a total redesign. Working closely with the product designer, who was very much of a mind with me with respect to appearance and usability, we were able to bring the product from its initial state (which I also designed) to where it is now, which I feel is a very usable and friendly experience, given the complexity of the process itself.