I speak as a former full time software designer and developer.
Yes, some changes are not optimal for some people, but you have to look at the big picture.
You get exponentially more productivity from developers who are having fun than from people who are just doing their job. From my point of view, the overall product progress we are getting from the team far outweighs the inconvenience of a constantly shifting landscape.
Sometimes it its just easier to do something and redo it later if is turns out to be a bad idea. This is what Beta software is all about.