Not directly related to your point but.... I think it comes down to what percent of users have more than 4 spaces or wouldn't mind only using 4.
The concept of making the typical use case better at the expense of completeness seems to be very much in line with Apple's UI decisions.
I can't remember where I read this (I think it was in "The Inmates Are Running The Asylum" - a great UI design book). But he makes the point that as programmers we are trained to think about edge cases so we often bring this over to UI design where it's better to think of the typical case.
Basically, when given two options in UI design:
1. satisfy 80% of users with a simple design
2. accomodate all users, but add a little complexity
I think this is also part of why a lot of typical techie types dislike Apple. Apple tends to go with #1, and often times techies are the edge cases who would be frustrated by it.
The concept of making the typical use case better at the expense of completeness seems to be very much in line with Apple's UI decisions.
I can't remember where I read this (I think it was in "The Inmates Are Running The Asylum" - a great UI design book). But he makes the point that as programmers we are trained to think about edge cases so we often bring this over to UI design where it's better to think of the typical case.
Basically, when given two options in UI design:
1. satisfy 80% of users with a simple design
2. accomodate all users, but add a little complexity
Choose 1