Not a bad design but can improve...

Here is an example of an object that I thought has some flaws to it. This is a Yamaha electronic 88-keys keyboard.

From a visibility point of view, it has buttons that look like a button you can press, knobs that look like a knob you can turn, so in that perspective, it was fine.

The affordances was fine too given there are piano keys that I can afford to press with leisure.

Mappings were fine with the same reasons from visibility and affordances.

This keyboard looks like it can do a lot of things beside playing the keyboard like pressing the keys and make music. It looks like the keyboard was designed to do multitude of things; however, the only thing I know how to do is turn on the keyboard and play a song. I wanted to do more with it but it just have way too many buttons and functions that I don't have the time to learn it. As Dan Norman's book have mentioned, as functionality increases in an object, it also increases complexities and frustration.

In addition to that, there is a graphical interface in the center to tell me what instrument I am currently playing and etc, but the problem is that there is lack of feedback from the object. For example, when I press something that I cannot do, the interface does not tell me I am doing something wrong, it just doesn't do anything. I'm not sure that's a good thing in my case because I would like some sort of feedback.

The instructions on the panel tells me what types of instrument refers to what number; however, it does not tell me how I can select them.

In conclusion, I think this keyboard is finely built; however, I think they can improve upon their design just a little bit more. I have always been a Yamaha fans when it comes to piano and keyboards and still am.