The software isn't finished until the last user is dead.
- Anonymous
 
... the designer of a new system must not only be the implementor and the first large-scale user; the designer should also write the first user manual. ... If I had not participated fully in all these activities, literally hundreds of improvements would never have been made, because I would never have thought of them or perceived why they were important.
- Donald E. Knuth
 
Version 1 of any software is full of bugs. Version 2 fixes all the bugs and is great. Version 3 adds all the things users ask for, but hides all the great stuff in Version 2.
- Fred Blechman
 
Never present a power-user option in such a way that normal users must learn all about it in order to know they don't need to use it.
- Bruce Tognazzini - From TOG on Interface, p 269.
 
If you don't have a good system, make sure you get good users.
- Anonymous