Earlier quoted context omitted.
> every project has three levers: budget, timeliness, features. Choose two You forgot about quality. It can blow the other 3 out of the water.
Quality is implied within the feature/scope grouping. Its always a three leg stool trade off for balance. Changing your quality output is just reducing or adding to scope requirements. Budget = Resuorces / Time = Time / Scope = Quality
Quality could be grouped with features as "usefulness" of the software. Low quality software is unusable, or more expensive to use.
Timeliness has an equally direct impact on software value, but in this planning context it makes sense to distinguish what is delivered and when it is delivered.