If you have to implement a feature and you have two ways to do it: the easy way or the hard way, which one would you pick?
As a developer, when you look at your product you see its architecture. You see how all the parts fit together. Likely, you were involved in coming up with this architecture. You’re a believer.
So, if software is beautiful from the inside, is it also beautiful from the outside?
If a user asks you for a feature that does not fit your current software architecture — does your software architecture need adjusting, or does the user need adjusting?
If you walk into a plane, would you prefer to walk left, into the cockpit where you have full control over everything, have access to all the sliders and sticks — or right, where all you can do is push a button to call for a stewardess to bring you coffee?
What does your wife prefer: flexibility or simplicity?
If you give a non-technical person the choice between an Android or iPhone — which one would they pick?
Does your mother know how to use a VCR or DVD recorder?
Read the inmates are running the asylum. I bet it will change your view on the importance of user interaction design forever.