a) They did not consider the users instead they were building the interface for themselves. They should have done some type of research to find out what the users want and who they are and not make the assumption that "they are like us" becasue they are not.
b) This part is really common sense, of course the old people found it hard to read, they are getting older and their eyesight is diminishing. Again put your user's need into consideration which in this case was not done.
c)Again think about your user and not assume that "they should know" because you know it and it is so easy to you. The user are used to seeing things in a particular way, try to stay with that style, this makes it easier for them to learn because they can relate it to something they are already familiar with. Remember the user and not what you think they know or what, investigate research do surveys or questionaire to get a better idea of what the users need are.
To add to part c, this also particularly violates the UI rule "show the knowledge". It is apparent that the interface didn't specify this new way of using OK and Cancel. Therefore, without showing where to click for OK and where to click for Cancel, the user could easily have problems figuring what does what. Even if they changed the place to click, not showing the user where this new place was is just plain bad UI.
Nice – other good answers, but these are nice. (c) has lots of errors in it. There's one more in particular that we talked about in class. Mark Guzdial
Could it be that programmers should follow approved guidelines, such
as keeping things labelled, always putting OK/cancel buttons in lower
right hand corner, etc.? Also, code to people's expectations - do
make things work like they expect them to, that will make things
easier and more efficient for them.
a) Look at your users then look around yourself then stary looking your users fron top to bottom (vertically) then look yourself vertically. Now look into the eyes of your users find something in their eyes. Their eyes are tring to sya you something, feel it, read it, understand it. Now observe their lips, teeth and finally tongue. Now ask yourself "Did you find anything so far". If yes, pay them; if not get from them. USER are stupid, ediot, and shy ..so as a designer you take the advantage of all these properties and design something which is not understandable to you, but your users can make a guess on your design. Systems are dump, they are garbage; compare systems with your users.... see who is smart? "SYSTEMS" or "USERS". .......
...... To be continued.