What IT has taught me

Eat your own dog food

This saying states that you should use your own products internally, as much as possible. Not only does this show pride in your work, but you also get to know your product from the user's point of view. Every company should do this, and this way you can get a first hand experience of how to improve the software, what other features to add, and whether those "life-altering" features that you decided to add, actually alter the user's life for the better.
One should not shy away of using the products, and also checking their compatibility issues with other products. It is quite unfortunate that people who build software for specific reasons, that they cannot use them each and every day. It might be an adequate punishment in Dante's Inferno ,seeing some software developer having to use their own software each and every day. If you were to be the one using that software each and every day, maybe you would put less images, and bigger text. Or maybe you would make that airplane boarding software less fancy, and more responsive. Or maybe you would make that online booking system less Web 2.0, and more reliable.
And even if at the end of the day you get to use your own software, and you like it, do not forget the blind people, or colour blind individuals, or people who have problem using a mouse, or people who do not understand your main language....
if everyone working in software were to consider a bit more the users, and as many of them as possible, I am sure that the quality of it would greatly improve.