Not exactly the best design...
...for people with back or hip problems. No back support at all, so many elderly and/or disabled will simply fall off.
Then there is the problem of people who can't walk at all. From a normal chair, you can get them to an upright position, then sit them down into a conventional wheelchair. How are you supposed to safely and comfortably move them forward onto the seat on this machine? It would be much the same as trying to sit them on a small motorcycle.